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Chapter 2 Programming ExercisesPE 2--‐1/* Programming Exercise 2-1 */#include<stdio.h> intmain(void){ printf("GustavMahler\n");printf("Gustav\nMahler\n"); printf("Gustav");printf("Mahler\n");return 0;}PE 2--‐3/* Programming Exercise 2-3 */#include<stdio.h> intmain(void){ int ageyears; /* age inyears */ int agedays; /*age in days *//* large ages may require the long type*/ ageyears = 101; agedays = 365 * ageyears;printf("An age of %d years is %d days.\n", ageyears, agedays); return 0;}PE 2--‐4/* Programming Exercise 2-4 */#include<stdio.h>voidjolly(void);voiddeny(void);int main(void){ jolly();jolly();jolly();deny();return0; }void jolly(void){printf("For he's a jolly good fellow!\n"); }void deny(void){printf("Which nobody can deny!\n");}PE 2--‐6/* Programming Exercise 2-6 */#include<stdio.h> intmain(void){ inttoes;toes =10;printf("toes = %d\n", toes);printf("Twice toes = %d\n", 2 * toes); printf("toes squared = %d\n", toes * toes); return 0;}/* or create two more variables, set them to 2 * toes and toes * toes */PE 2--‐8/* Programming Exercise 2-8 */#include<stdio.h>voidone_three(void); voidtwo(void); intmain(void){printf("startingnow:\n");one_three();printf("done!\n");return 0;}void one_three(void){printf("one\n");two();printf("three\n");}void two(void){printf("two\n");}Chapter 3 Programming ExercisesPE 3--‐2/* Programming Exercise 3-2 */#include<stdio.h> intmain(void){intascii;printf("Enter an ASCII code: ");scanf("%d", &ascii);printf("%d is the ASCII code for %c.\n", ascii, ascii); return 0;}PE 3--‐4/* Programming Exercise 3-4 */#include<stdio.h> intmain(void){ float num;printf("Enter a floating-point value: ");scanf("%f", &num);printf("fixed-point notation: %f\n",num); printf("exponentialnotation: %e\n", num); printf("pnotation: %a\n", num); return 0;}PE 3--‐6/* Programming Exercise 3-6 */#include<stdio.h> intmain(void){float mass_mol = 3.0e-23; /* mass of water moleculein grams */ float mass_qt = 950; /* mass of quartof water in grams */ float quarts; float molecules;printf("Enter the number of quarts of water: ");scanf("%f", &quarts);molecules = quarts * mass_qt / mass_mol;printf("%f quarts of water contain %e molecules.\n", quarts, molecules); return 0;}Chapter 4 Programming ExercisesPE 4--‐1/* Programming Exercise 4-1 */#include<stdio.h> intmain(void){ charfname[40];charlname[40];printf("Enter your firstname: "); scanf("%s",fname); printf("Enter yourlast name: "); scanf("%s",lname); printf("%s, %s\n",lname, fname); return 0;}PE 4--‐4/* Programming Exercise 4-4 */#include<stdio.h> intmain(void){ floatheight;charname[40];printf("Enter your height ininches: "); scanf("%f", &height);printf("Enter your name: ");scanf("%s", name);printf("%s, you are %.3f feet tall\n", name, height / 12.0); return0;}PE 4--‐7/* Programming Exercise 4-7 */#include<stdio.h>#include<float.h> intmain(void){ float ot_f = 1.0 /3.0; double ot_d= 1.0 / 3.0;printf(" float values:");printf("%.4f %.12f %.16f\n", ot_f, ot_f, ot_f); printf("double values: ");printf("%.4f %.12f %.16f\n", ot_d,ot_d, ot_d); printf("FLT_DIG: %d\n",FLT_DIG); printf("DBL_DIG: %d\n",DBL_DIG); return 0;}Chapter 5 Programming Exercises PE 5--‐1/* Programming Exercise 5-1 */#include<stdio.h> intmain(void){ const intminperhour = 60;int minutes, hours,mins;printf("Enter the number of minutes to convert: "); scanf("%d", &minutes);while (minutes > 0 ){ hours = minutes /minperhour; mins =minutes % minperhour;printf("%d minutes = %d hours, %d minutes\n", minutes, hours, mins); printf("Enter next minutes value (0 to quit): "); scanf("%d", &minutes);}printf("Bye\n");return0;}PE 5--‐3/* Programming Exercise 5-3 */#include<stdio.h> intmain(void){ const intdaysperweek = 7;int days, weeks,day_rem;printf("Enter the number ofdays: "); scanf("%d", &days);while (days > 0){ weeks = days /daysperweek; day_rem= days % daysperweek;printf("%d days are %d weeks and %ddays.\n", days, weeks, day_rem);printf("Enter the number of days (0 or less to end): "); scanf("%d", &days);}printf("Done!\n");return 0;}PE 5--‐5/* Programming Exercise 5-5*/ #include <stdio.h>int main(void) /* finds sum of first n integers */{int count,sum;int n;printf("Enter the upperlimit: "); scanf("%d", &n);count = 0; sum= 0; while(count++ < n) sum =sum + count; printf("sum= %d\n", sum); return 0;}PE 5--‐7/* ProgrammingExercise 5-7 */#include <stdio.h>voidshowCube(double x);int main(void) /* finds cube of entered number */ { double val;printf("Enter a floating-pointvalue: "); scanf("%lf", &val);showCube(val); return 0; }void showCube(double x){printf("The cube of %e is %e.\n", x, x*x*x );}Chapter 6 Programming ExercisesPE 6--‐1/* pe6-1.c *//* this implementation assumes the character codes */ /* are sequential, as they are in ASCII. */#include <stdio.h>#define SIZE 26 intmain( void ) { charlcase[SIZE]; int i;for (i = 0; i < SIZE;i++) lcase[i] = 'a'+ i; for (i = 0; i <SIZE; i++)printf("%c", lcase[i]);printf("\n");return 0;}PE 6--‐3/* pe6-3.c *//* this implementation assumes the character codes */ /* are sequential, as they are in ASCII. */#include<stdio.h> intmain( void ){ char let= 'F'; charstart; charend;for (end = let; end >= 'A'; end--){for (start = let; start >= end; start--) printf("%c", start);printf("\n");}return0;}PE 6--‐6/* pe6-6.c */#include<stdio.h> intmain( void ){ int lower, upper,index; int square,cube;printf("Enter startinginteger: "); scanf("%d",&lower); printf("Enterending integer: ");scanf("%d", &upper);printf("%5s %10s %15s\n", "num","square", "cube"); for (index = lower;index <= upper; index++){ square =index * index;cube = index * square;printf("%5d %10d %15d\n", index, square, cube);}return0;}PE 6--‐8/* pe6-8.c */#include<stdio.h> intmain( void ){ double n, m;doubleres;printf("Enter a pair of numbers: ");while (scanf("%lf %lf", &n, &m) == 2){res = (n - m) / (n * m);printf("(%.3g - %.3g)/(%.3g*%.3g) = %.5g\n", n, m, n, m, res); printf("Enter next pair (non-numeric to quit): "); }return 0;}PE 6--‐11/* pe6-11.c */#include<stdio.h>#defineSIZE 8 intmain( void ){ intvals[SIZE];int i;printf("Please enter %d integers.\n",SIZE); for (i = 0; i < SIZE; i++)scanf("%d", &vals[i]);printf("Here, in reverse order, are the values you entered:\n"); for (i = SIZE - 1; i >= 0; i--)printf("%d ", vals[i]); printf("\n"); return 0;}PE 6--‐13/* pe6-13.c *//* This version starts with the 0 power */#include<stdio.h>#defineSIZE 8 intmain( void ){inttwopows[SIZE];int i;int value = 1; /* 2 to the 0 */for (i = 0; i < SIZE; i++){ twopows[i]= value; value*= 2;}i =0;do{printf("%d ",twopows[i]); i++; } while (i < SIZE);printf("\n"); return 0;}PE 6--‐14/* pe-14.c *//* Programming Exercise 6-14 */ #include<stdio.h>#defineSIZE 8 intmain(void){ doublearr[SIZE];doublearr_cumul[SIZE];int i;printf("Enter %d numbers:\n", SIZE);for (i = 0; i < SIZE; i++){printf("value #%d: ", i + 1); scanf("%lf", &arr[i]); /* or scanf("%lf", arr + i);*/}arr_cumul[0] = arr[0]; /* set first element */ for (i = 1; i < SIZE; i++)arr_cumul[i] = arr_cumul[i-1] + arr[i];for (i = 0; i < SIZE;i++) printf("%8g ",arr[i]); printf("\n"); for(i = 0; i < SIZE; i++)printf("%8g ", arr_cumul[i]);printf("\n");return 0;}PE 6--‐16/* pe6-16.c */#include <stdio.h>#define RATE_SIMP 0.10#defineRATE_COMP0.05 #defineINIT_AMT 100.0int main( void ){double daphne =INIT_AMT;double deidre =INIT_AMT; intyears = 0;while (deidre <= daphne){ daphne +=RATE_SIMP * INIT_AMT;deidre += RATE_COMP *deidre;++years;}printf("Investment values after %d years:\n",years); printf("Daphne: $%.2f\n", daphne);printf("Deidre: $%.2f\n", deidre); return 0;}Chapter 7 Programming ExercisesPE 7--‐1/* ProgrammingExercise 7-1 */#include <stdio.h> intmain(void){ char ch;int sp_ct = 0;int nl_ct = 0;int other = 0;while ((ch =getchar()) != '#'){if (ch == ' ')sp_ct++; else if(ch == '\n')nl_ct++; elseother++;}printf("spaces: %d, newlines: %d, others: %d\n", sp_ct, nl_ct, other); return0;}PE 7--‐3/* Programming Exercise 7-3 */#include<stdio.h> intmain(void){ int n;double sumeven =0.0; int ct_even= 0; doublesumodd = 0.0;int ct_odd = 0;while (scanf("%d", &n) == 1 && n != 0) {if (n % 2 == 0){sumeven += n;++ct_even;}else // n % 2 is either 1 or -1{sumodd += n;++ct_odd;} }printf("Number of evens: %d",ct_even); if (ct_even > 0)printf(" average: %g", sumeven /ct_even); putchar('\n');printf("Number of odds: %d",ct_odd); if (ct_odd > 0)printf(" average: %g", sumodd /ct_odd); putchar('\n');printf("\ndone\n");return0;}PE 7--‐5/* Programming Exercise 7-5 */#include<stdio.h> intmain(void){ charch; intct1 = 0;int ct2 = 0;while ((ch=getchar())!= '#'){switch(ch){case '.' : putchar('!');++ct1; break;case '!' : putchar('!');putchar('!');++ct2; break;default : putchar(ch);} }printf("%d replacement(s) of . with !\n", ct1); printf("%d replacement(s) of ! with !!\n", ct2); return0;}PE 7--‐7// Programming Exercise 7-7#include <stdio.h>#define BASEPAY 10 // $10 per hour#define BASEHRS 40 // hours at basepay#define OVERTIME 1.5 // 1.5 time#define AMT1 300 // 1st rate tier#define AMT2 150 // 2st rate tier#define RATE1 0.15 // rate for 1st tier#define RATE2 0.20 // rate for 2ndtier #define RATE3 0.25 // rate for3rd tier int main(void){doublehours;double gross;double net;double taxes;printf("Enter the number of hours worked thisweek: "); scanf("%lf", &hours); if (hours<= BASEHRS) gross = hours * BASEPAY;elsegross = BASEHRS * BASEPAY + (hours - BASEHRS) * BASEPAY * OVERTIME; if (gross <= AMT1) taxes = gross * RATE1; else if (gross <= AMT1 + AMT2)taxes = AMT1 * RATE1 + (gross - AMT1)* RATE2; elsetaxes = AMT1 * RATE1 + AMT2 * RATE2 + (gross - AMT1- AMT2) * RATE3; net = gross - taxes;printf("gross: $%.2f; taxes: $%.2f; net: $%.2f\n", gross, taxes, net); return0;}PE 7--‐9/* Programming Exercise 7-9 */#include<stdio.h>#include<stdbool.h> intmain(void){intlimit;int num;int div;bool numIsPrime; // use int if stdbool.h not availableprintf("Enter a positive integer: ");while (scanf("%d", &limit) == 1 &&limit > 0){if (limit > 1)printf("Here are the prime numbers up through %d\n", limit); elseprintf("No primes.\n");for (num = 2; num <= limit;num++){for (div = 2, numIsPrime = true; (div * div) <= num; div++) if (num % div == 0) numIsPrime = false; if (numIsPrime)printf("%d is prime.\n", num);}printf("Enter a positive integer (q to quit): ");}printf("Done!\n");return 0;}PE 7--‐11/* pe7-11.c *//* Programming Exercise 7-11 */#include<stdio.h>#include<ctype.h> intmain(void){const doubleprice_artichokes = 2.05;const double price_beets =1.15; const doubleprice_carrots = 1.09; constdouble DISCOUNT_RATE =0.05; const double under5 =6.50; const double under20 =14.00; const double base20 =14.00; const double extralb =0.50;charch;doublelb_artichokes = 0;double lb_beets = 0;double lb_carrots =0; double lb_temp;double lb_total;doublecost_artichokes;double cost_beets;doublecost_carrots;double cost_total;double final_total;double discount;double shipping;printf("Enter a to buy artichokes, b for beets, "); printf("c for carrots, q to quit: "); while ((ch = getchar()) != 'q' && ch != 'Q') { if (ch == '\n')continue; while(getchar() != '\n')continue; ch =tolower(ch); switch(ch) {case 'a' : printf("Enter pounds of artichokes: "); scanf("%lf", &lb_temp); lb_artichokes += lb_temp; break;case 'b' : printf("Enter pounds of beets:"); scanf("%lf", &lb_temp); lb_beets += lb_temp; break;case 'c' : printf("Enter pounds of carrots: "); scanf("%lf",&lb_temp); lb_carrots +=lb_temp; break;default : printf("%c is not a valid choice.\n", ch);}printf("Enter a to buy artichokes, b for beets, "); printf("c for carrots, q to quit: ");}cost_artichokes = price_artichokes *lb_artichokes; cost_beets = price_beets *lb_beets; cost_carrots = price_carrots *lb_carrots; cost_total = cost_artichokes +cost_beets + cost_carrots; lb_total =lb_artichokes + lb_beets + lb_carrots; if(lb_total <= 0) shipping = 0.0; else if(lb_total < 5.0) shipping = under5; else if(lb_total < 20) shipping = under20; elseshipping = base20 + extralb *lb_total; if (cost_total > 100.0)discount = DISCOUNT_RATE* cost_total; else discount =0.0;final_total = cost_total + shipping - discount; printf("Your order:\n");printf("%.2f lbs of artichokes at $%.2f per pound:$ %.2f\n", lb_artichokes,price_artichokes, cost_artichokes); printf("%.2flbs of beets at $%.2f per pound: $%.2f\n",lb_beets, price_beets, cost_beets); printf("%.2flbs of carrots at $%.2f per pound: $%.2f\n",lb_carrots, price_carrots, cost_carrots);printf("Total cost of vegetables: $%.2f\n",cost_total); if (cost_total > 100)printf("V olume discount: $%.2f\n", discount); printf("Shipping: $%.2f\n", shipping); printf("Total charges:$%.2f\n", final_total); return 0; }Chapter 8 Programming ExercisesPE 8--‐1/* Programming Exercise 8-1 */#include <stdio.h>int main(void) { int ch;int ct = 0; while ((ch= getchar()) != EOF)ct++;printf("%d characters read\n", ct);return0;}PE 8--‐3/* Programming Exercise 8-3 *//* Using ctype.h eliminates need to assume consecutive coding */#include <stdio.h>#include<ctype.h> intmain(void) { intch; unsignedlong uct = 0;unsigned long lct= 0; unsignedlong oct = 0;while ((ch =getchar()) != EOF) if(isupper(ch)) uct++;else if (islower(ch))lct++; elseoct++;printf("%lu uppercase characters read\n", uct);printf("%lu lowercase characters read\n", lct);printf("%lu other characters read\n", oct);return0;}/* or you could useif (ch >= 'A' && ch<= 'Z') uct++;else if (ch >= 'a' && ch<= 'z') lct++; elseoct++;*/PE 8--‐5/* Programming Exercise 8-5 *//* binaryguess.c -- an improved number-guesser *//* but relies upon truthful, correct responses */#include <stdio.h>#include <ctype.h> intmain(void) { int high= 100; int low = 1;int guess = (high + low)/ 2; char response;printf("Pick an integer from 1 to 100. I will try to guess "); printf("it.\nRespond with a y if my guess is right, with"); printf("\na h if it is high, and with an l if it is low.\n"); printf("Uh...is your number %d?\n", guess);while ((response = getchar()) != 'y') /* get response */{if (response == '\n')continue;if (response != 'h' && response != 'l'){printf("I don't understand that response. Please enter h for\n"); printf("high, l for low, or y for correct.\n"); continue;}if (response == 'h')high = guess - 1;else if (response == 'l')low = guess + 1;guess = (high + low) /2;printf("Well, then, is it %d?\n", guess);}printf("I knew I could do it!\n");return 0;}PE 8--‐7/* Programming Exercise 8-7 */#include <stdio.h>#include <ctype.h>#include <stdio.h>#define BASEPAY1 8.75 // $8.75 per hour#define BASEPAY2 9.33 // $9.33 per hour#define BASEPAY3 10.00 // $10.00 per hour#define BASEPAY4 11.20 // $11.20 per hour#define BASEHRS 40 // hours at basepay#define OVERTIME 1.5 // 1.5 time#define AMT1 300 // 1st rate tier#define AMT2 150 // 2st rate tier#define RATE1 0.15 // rate for 1st tier#define RATE2 0.20 // rate for2nd tier #define RATE3 0.25 //rate for 3rd tier int getfirst(void); voidmenu(void); int main(void){ doublehours;doublegross;double net;doubletaxes;double pay;charresponse;menu();while ((response = getfirst()) != 'q'){if (response == '\n') /* skip over newlines */ continue;response = tolower(response); /* accept A as a, etc. */ switch (response){case 'a': pay = BASEPAY1;break; case 'b': pay =BASEPAY2; break; case 'c': pay= BASEPAY3; break; case 'd':pay = BASEPAY4; break;default : printf("Please enter a, b, c, d, or q.\n"); menu();continue; // go to beginning of loop}printf("Enter the number of hours worked thisweek: "); scanf("%lf", &hours); if(hours <= BASEHRS) gross = hours * pay;elsegross = BASEHRS * pay + (hours - BASEHRS) *pay * OVERTIME; if (gross <= AMT1) taxes= gross * RATE1; else if (gross <= AMT1 + AMT2)taxes = AMT1 * RATE1 + (gross - AMT1) *RATE2; elsetaxes = AMT1 * RATE1 + AMT2 * RATE2 + (gross - AMT1 - AMT2) * RATE3; net = gross - taxes;printf("gross: $%.2f; taxes: $%.2f; net: $%.2f\n", gross, taxes, net); menu(); }printf("Done.\n");return0;}void menu(void){printf("********************************************************""*********\n");printf("Enter the letter corresponding to the desired payrate"" or action:\n");printf("a) $%4.2f/hr b) $%4.2f/hr\n",BASEPAY1, BASEPAY2);printf("c) $%5.2f/hr d) $%5.2f/hr\n",BASEPAY3, BASEPAY4); printf("q)quit\n");printf("********************************************************""*********\n");}int getfirst(void){intch;ch = getchar();while (isspace(ch))ch = getchar();while (getchar() !='\n') continue;return ch;}Chapter 9 Programming Exercises PE 9--‐1/* Programming Exercise 9-1 */#include <stdio.h>double min(double,double); int main(void){double x, y; printf("Entertwo numbers (q to quit): "); while(scanf("%lf %lf", &x, &y) == 2){ printf("The smaller numberis %f.\n", min(x,y)); printf("Next two values (q to quit): ");}printf("Bye!\n");return0;}double min(double a, double b){return a < b ? a : b;}/* alternativeimplementation doublemin(double a, double b){ if (a <b)return a;elsereturn b;}*/PE 9--‐3/* Programming Exercise 9-3 */#include <stdio.h>void chLineRow(char ch, int c,int r); int main(void){ char ch; int col, row;printf("Enter a character (# to quit):"); while ( (ch = getchar()) != '#'){ if (ch== '\n')continue;printf("Enter number of columns and number of rows: "); if (scanf("%d %d", &col,&row) != 2) break; chLineRow(ch, col, row);printf("\nEnter next character (# to quit): ");}printf("Bye!\n");return0;}// start rows and cols at 0void chLineRow(char ch, intc, int r){int col, row;for (row = 0; row < r ; row++){for (col = 0; col < c;col++) putchar(ch);putchar('\n');}return;}PE 9--‐5/* Programming Exercise 9-5 */#include <stdio.h>void larger_of(double *p1, double*p2); int main(void){double x, y; printf("Entertwo numbers (q to quit): "); while(scanf("%lf %lf", &x, &y) == 2){larger_of(&x, &y);printf("The modified values are %f and %f.\n", x, y); printf("Next two values (q to quit): ");}printf("Bye!\n");return0;}void larger_of(double *p1, double *p2){ if(*p1 > *p2)*p2 = *p1;else*p1 = *p2;}// alternatively:/*void larger_of(double *p1, double *p2){*p1= *p2 = *p1 > *p2 ? *p1 : *p2;}*/PE 9--‐8/* Programming Exercise 9-8*/ #include <stdio.h>double power(double a, int b); /* ANSIprototype */ int main(void) { double x, xpow;int n; printf("Enter a number and the integer power"); printf(" to which\nthe number willbe raised. Enter q"); printf(" to quit.\n");while (scanf("%lf%d", &x, &n) == 2){ xpow = power(x,n); /* function call*/ printf("%.3g to the power %d is %.5g\n", x,n, xpow); printf("Enter next pair of numbersor q to quit.\n");} printf("Hope you enjoyed this powertrip -- bye!\n"); return 0;} double power(double a, int b) /* function definition */{ doublepow = 1;int i; if(b == 0){ if (a== 0)printf("0 to the 0 undefined; using 1 as the value\n"); pow = 1.0; } else if (a == 0) pow = 0.0; else if (b > 0) for(i = 1; i <= b; i++) pow *= a; else /* b < 0 */ pow = 1.0 / power(a, - b);return pow; /* return the value of pow */}PE 9--‐10/* Programming Exercise 9-10 */#include <stdio.h> voidto_base_n(int x, int base); intmain(void) { int number; int b;int count; printf("Enter aninteger (q to quit):\n"); while(scanf("%d", &number) == 1){ printf("Enter number base(2-10): "); while ((count =scanf("%d", &b))== 1&& (b < 2 || b > 10)){printf("base should be in the range 2-10: ");} if(count != 1)break;printf("Base %d equivalent:", b); to_base_n(number, b);putchar('\n');printf("Enter an integer (q to quit):\n");}printf("Done.\n"); return 0;}void to_base_n(int x, int base) /* recursive function */ { int r; r = x % base;if (x >= base)to_base_n(x / base,base); putchar('0' + r);return;}Chapter 10 Programming ExercisesPE 10--‐1/* Programming Exercise 10-1 */#include <stdio.h>#define MONTHS 12 // number ofmonths in a year #define YRS 5 //number of years of data int main(void){// initializing rainfall data for 2010 - 2014const float rain[YRS][MONTHS] = {{4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},{8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},{9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},{7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},{7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}}; int year,month; floatsubtot, total;printf(" YEAR RAINFALL(inches)\n"); for (year = 0, total = 0;year < YRS; year++){ /* for each year, sum rainfall for eachmonth */ for (month = 0, subtot = 0; month < MONTHS; month++) subtot += *(*(rain +year) + month); printf("%5d %15.1f\n", 2010 + year, subtot);total += subtot; /* total for all years */}printf("\nThe yearly average is %.1f inches.\n\n",total/YRS); printf("MONTHLY A VERAGES:\n\n");printf(" Jan Feb Mar Apr May Jun Jul Aug Sep Oct "); printf(" Nov Dec\n");for (month = 0; month < MONTHS; month++){ /* for each month, sum rainfall overyears */ for (year = 0, subtot =0; year < YRS;year++) subtot += *(*(rain + year) + month); printf("%4.1f ", subtot/YRS);}printf("\n");return 0;}PE 10--‐3/* Programming Exercise 10-3 */#include <stdio.h>#define LEN 10int max_arr(const int ar[],int n); void show_arr(constint ar[], int n);int main(void){int orig[LEN] ={1,2,3,4,12,6,7,8,9,10}; int max;show_arr(orig, LEN);max = max_arr(orig, LEN);printf("%d = largest value\n",max);return0;}int max_arr(const int ar[], int n){ int i;int max =ar[0];/* don't use 0 as initial max value -- fails if all array values are neg */ for (i = 1; i < n;i++) if (max <ar[i]) max =ar[i]; return max;}void show_arr(const int ar[], int n){ int i; for (i= 0; i < n; i++)printf("%d ", ar[i]);putchar('\n');}。

第二章：开始学习C++ n”；}<<endl;return 0;}double C2F(double t){return *t+32;}<<endl;return 0;}double convert(double t){return 63240*t;n";return 0;}style(miles per gallon):"<<endl;cout<<Euro_style<<" L/100Km = "<<*Euro_style<<" mpg\n";return 0;}Enter the automobile gasoline consumption figure inEuropean style(liters per 100 kilometers):Converts to . style(miles per gallon):L/100Km = mpgPress any key to continuestyle(miles per gallon):";double US_style;cin>>US_style;cout<<"Converts to European style(miles per gallon):"<<endl;cout<<US_style<<" mpg = "<< *US_style<<"L/100Km\n";return 0;}style(miles per gallon):19Converts to European style(miles per gallon):19 mpg = 100KmPress any key to continue第四章复合类型n";return 0;}rand<<endl<<snack[i].weight<<endl<<snack[i].calory<<endl<<endl;}return 0;}rand="A";eight=;snack[0].calory=200;snack[1].brand="B";snack[1].weight=;snack[1].calory=400;snack[2].brand="C";snack[2].weight=;snack[2].calory=500;for(int i=0;i<3;i++){cout << " brand: " << snack[i].brand << endl;cout << " weight: " << snack[i].weight << endl;cout << " calorie: " << snack[i].calory << endl<<endl;}delete [] snack;return 0;}et();car* ps=new car[num];for(int i=0;i<num;++i){cout<<"Car #"<<i+1<<":\n";cout<<"Please enter the make: ";getline(cin,ps[i].name);cout<<"Please enter the year made: ";(cin>>ps[i].year).get();}cout<<"Here is your collection:\n";for(int i=0;i<num;++i)cout<<ps[i].year<<" "<<ps[i].name<<endl;delete [] ps;return 0;}n";return 0;}n";return 0;};for(int k=0;k<=i;++k)cout<<"*";cout<<endl;}return 0;}。

第一章概览编程练习1．您刚刚被MacroMuscle有限公司（Software for Hard Bodies）聘用。

该公司要进入欧洲市场，需要一个将英寸转换为厘米(1英寸= cm)的程序。

他们希望建立的该程序可提示用户输入英寸值。

您的工作是定义程序目标并设计该程序（编程过程的第1步和第2步）。

1.将英寸值转化为厘米值2.显示“输入英寸值”->得到该值->转换为厘米值->存储->告知用户已结束.第二章 C语言概述编程练习1．编写一个程序，调用printf()函数在一行上输出您的名和姓，再调用一次printf()函数在两个单独的行上输出您的名和姓，然后调用一对printf()函数在一行上输出您的名和姓。

输出应如下所示（当然里面要换成您的姓名）：Anton BrucknerAntonBrucknerAnton Bruckner第一个输出语句'第二个输出语句仍然是第二个输出语句第三个和第四个输出语句#include<>int main(void){、printf("He Jin\n");printf("He\n");printf("Jin\n");printf("He Jin\n");return(0);}，2．编写一个程序输出您的姓名及地址。

#include<>int main(void){printf("Name:He Jin\n");…printf("Address:CAUC\n");return(0);}3．编写一个程序，把您的年龄转换成天数并显示二者的值。

不用考虑平年( fractional year)和闰年(leapyear)的问题。

#include<>（int main(void){int age=22;printf("Age:%d\n",age);printf("Day:%d\n",age*356);return(0);}%4．编写一个能够产生下面输出的程序：For he's a jolly good fellow!For he's a jolly good fellow!For he's a jolly good fellow!Which nobody can deny!程序中除了main()函数之外，要使用两个用户定义的函数：一个用于把上面的夸奖消息输出一次：另一个用于把最后一行输出一次。

cprimerplus习题答案cprimerplus习题答案C Primer Plus是一本经典的C语言教材，被广泛用于学习和教授C语言的人士。

这本书的习题是帮助读者巩固所学知识和提高编程能力的重要环节。

在这篇文章中，我将为大家提供一些C Primer Plus习题的答案，希望对正在学习C语言的读者有所帮助。

1. 习题1：编写一个程序，输出"Hello, World!"。

答案：```c#include <stdio.h>int main() {printf("Hello, World!");return 0;}```这是一个非常简单的程序，使用了C语言的标准库函数printf()来输出字符串。

2. 习题2：编写一个程序，输入两个整数，然后计算它们的和并输出。

答案：```c#include <stdio.h>int main() {int num1, num2, sum;printf("请输入两个整数：");scanf("%d %d", &num1, &num2);sum = num1 + num2;printf("它们的和是：%d", sum);return 0;}```这个程序使用了scanf()函数来接收用户输入的两个整数，并使用加法运算符计算它们的和，最后使用printf()函数输出结果。

3. 习题3：编写一个程序，输入一个整数，然后判断它是否为偶数并输出结果。

答案：```c#include <stdio.h>int main() {int num;printf("请输入一个整数：");scanf("%d", &num);if (num % 2 == 0) {printf("这是一个偶数。

【C++PrimerPlus】编程练习答案——第12章 1// chapter12_1_cow.h234 #ifndef LEARN_CPP_CHAPTER12_1_COW_H5#define LEARN_CPP_CHAPTER12_1_COW_H67class Cow {8private:9char name_[20];10char * hobby_;11double weight_;12public:13 Cow();14 Cow(const char * name, const char * hobby, double weight);15 Cow(const Cow & c);16 ~Cow();17 Cow & operator=(const Cow & c);18void showcow() const;19 };202122#endif//LEARN_CPP_CHAPTER12_1_COW_H232425// chapter12_1_cow.cpp2627 #include "chapter12_1_cow.h"28 #include <cstring>29 #include <iostream>3031 Cow::Cow() {32 name_[0] = '\0';33 hobby_ = nullptr;34 weight_ = 0;35 }3637 Cow::Cow(const char * name, const char * hobby, double weight) {38 strcpy(name_, name);39 hobby_ = new char[strlen(hobby)];40 strcpy(hobby_, hobby);41 weight_ = weight;42 }4344 Cow::Cow(const Cow &c) {45 strcpy(name_, _);46if (!hobby_) delete [] hobby_;47 hobby_ = new char[strlen(c.hobby_)];48 strcpy(hobby_, c.hobby_);49 weight_ = c.weight_;50 }5152 Cow::~Cow() {53delete [] hobby_;54 }5556 Cow & Cow::operator=(const Cow & c) {57 strcpy(name_, _);58if (!hobby_) delete [] hobby_;59 hobby_ = new char[strlen(c.hobby_)];60 strcpy(hobby_, c.hobby_);61 weight_ = c.weight_;62return *this;63 }6465void Cow::showcow() const {66using namespace std;67 cout << "name: " << name_ << endl68 << "hobby: " << hobby_ << endl69 << "weight: " << weight_ << endl;70 }7172// run7374void ch12_1() {75 Cow a("nma", "tennis", 70);76 Cow b("nmb", "football", 65);77 a.showcow();78 b.showcow();79 b = a;80 b.showcow();81 Cow c(a);82 c.showcow();83 }// chapter12_2_string2.h#ifndef LEARN_CPP_CHAPTER12_2_STRING2_H#define LEARN_CPP_CHAPTER12_2_STRING2_H#include <iostream>using std::istream;using std::ostream;class string2 {private:char * str;int len;static int num_strings;static const int CINLIM = 80;public:string2();string2(const string2 & s);string2(const char * s);~string2();int length() const {return len;}int charnum(char ch) const; // dstring2 & stringlow(); // bstring2 & stringup(); // cstring2 & operator=(const string2 & s);string2 & operator=(const char * s);char & operator[](int i);const char & operator[](int i) const;friend bool operator<(const string2 & s1, const string2 & s2); friend bool operator>(const string2 & s1, const string2 & s2); friend bool operator==(const string2 & s1, const string2 & s2); friend ostream & operator<<(ostream & os, const string2 & s); friend istream & operator>>(istream & is, string2 & s);friend string2 & operator+(string2 & s1, const string2 & s2); // a static int howmany();};#endif//LEARN_CPP_CHAPTER12_2_STRING2_H// chapter12_2_string2.cpp#include "chapter12_2_string2.h"#include <cstring>#include <cctype>int string2::num_strings = 0;string2::string2() {len = 4;str = new char[1];str[0] = '\0';++ num_strings;}string2::string2(const string2 &s) {len = s.length();str = new char[len + 1];std::strcpy(str, s.str);++ num_strings;}string2::string2(const char *s) {len = std::strlen(s);str = new char[len + 1];std::strcpy(str, s);++ num_strings;}string2::~string2() {delete [] str;-- num_strings;}string2 &string2::operator=(const string2 &s) {if (this == &s)return *this;delete [] str;len = s.length();str = new char[len + 1];std::strcpy(str, s.str);return *this;}string2 &string2::operator=(const char *s) {delete [] str;len = std::strlen(s);str = new char[len + 1];std::strcpy(str, s);return *this;}char &string2::operator[](int i) {return str[i];}const char &string2::operator[](int i) const {return str[i];}int string2::howmany() {return num_strings;}bool operator<(const string2 & s1, const string2 & s2) { return (std::strcmp(s1.str, s2.str) < 0);}bool operator>(const string2 & s1, const string2 & s2) { return s2 < s1;}bool operator==(const string2 & s1, const string2 & s2) { return (std::strcmp(s1.str, s2.str) == 0);}ostream & operator<<(ostream & os, const string2 & s) { os << s.str;return os;}istream & operator>>(istream & is, string2 & s) {char temp[string2::CINLIM];is.get(temp, string2::CINLIM);if (is)s = temp;while (is && is.get() != '\n')continue;return is;}int string2::charnum(char ch) const {int i = 0, num = 0;while (str[i] != '\0') {if (str[i] == ch)++ num;++ i;}return num;}string2 &string2::stringlow() {int i = 0;while (str[i] != '\0') {if (std::isalpha(str[i]))str[i] = std::toupper(str[i]);++ i;}return *this;}string2 &string2::stringup() {int i = 0;while (str[i] != '\0') {if (std::isalpha(str[i]))str[i] = std::tolower(str[i]);++ i;}}string2 & operator+(string2 & s1, const string2 & s2) {char * temp = new char[s1.len];std::strcpy(temp, s1.str);delete [] s1.str;s1.str = new char[s1.len + s2.len + 1];s1.len += s2.len;std::strcpy(s1.str, temp);std::strcat(s1.str, s2.str);return s1;}// runvoid ch12_2() {using namespace std;string2 s1(" and I am a C++ student.");string2 s2 = "Please enter your name: ";string2 s3;cout << s2;cin >> s3;string2 t("My name is ");s2 = t + s3;cout << s2 << ".\n";s2 = s2 + s1;s2.stringup();cout << "The string\n" << s2 << "\ncontains " << s2.charnum('A')<< " 'A' characters in it.\n";s1 = "red";string2 rgb[3] = {string2(s1), string2("green"), string2("blue")};cout << "Enter the name of a primary color for mixing light: ";string2 ans;bool success = false;while (cin >> ans) {ans.stringlow();for (int i = 0; i < 3; ++ i) {if (ans == rgb[i]) {cout << "That's right!\n";success = true;break;}}if (success)break;elsecout << "Try again!\n";}cout << "Bye\n";}1// chapter12_3_stock.h234void ch12_2() {5using namespace std;6 string2 s1(" and I am a C++ student.");7 string2 s2 = "Please enter your name: ";8 string2 s3;9 cout << s2;10 cin >> s3;11 string2 t("My name is ");12 s2 = t + s3;13 cout << s2 << ".\n";14 s2 = s2 + s1;15 s2.stringup();16 cout << "The string\n" << s2 << "\ncontains " << s2.charnum('A')17 << " 'A' characters in it.\n";18 s1 = "red";19 string2 rgb[3] = {string2(s1), string2("green"), string2("blue")};20 cout << "Enter the name of a primary color for mixing light: ";21 string2 ans;22bool success = false;23while (cin >> ans) {24 ans.stringlow();25for (int i = 0; i < 3; ++ i) {26if (ans == rgb[i]) {27 cout << "That's right!\n";28 success = true;29break;30 }31 }32if (success)34else35 cout << "Try again!\n";36 }37 cout << "Bye\n";38 }394041// chapter12_3_stock.cpp4243 #include "chapter12_3_stock.h"4445 #include <iostream>46 #include <cstring>4748 stock::stock() {49 company = new char[8];50 len = 7;51 strcpy(company, "no name");52 shares = 0;53 share_val = 0.0;54 total_val = 0.0;55 }5657 stock::stock(const char * co, long n, double pr) {58 len = strlen(co);59 company = new char[len + 1];60 strcpy(company, co);61if (n < 0) {62 std::cout << "Number of shares can't be negative; "63 << company << " shares set to 0.\n";64 shares = 0;65 }66else67 shares = n;68 share_val = pr;69 set_tot();70 }7172 stock::~stock() {73delete [] company;74 }7576void stock::buy(long num, double price) {77if (num < 0) {78 std::cout << "Number of shares purchased can't be nagetive. "79 << "Transaction is aborted.\n";80 }81else {82 shares += num;83 share_val = price;84 set_tot();85 }86 }8788void stock::sell(long num, double price) {89using std::cout;90if (num < 0) {91 cout << "Number of shares sold can't be negative. "92 << "Transaction is aborted.\n";93 }94else {95 shares -= num;96 share_val = price;97 set_tot();98 }99 }100101void stock::update(double price) {102 share_val = price;103 set_tot();104 }105106void stock::show() const {107using std::cout;108using std::ios_base;109 ios_base::fmtflags orig = cout.setf(ios_base::fixed, ios_base::floatfield); 110 std::streamsize prec = cout.precision(3);111 cout << "Company: " << company112 << " Shares: " << shares << '\n';113 cout << "Shares Prices: $" << share_val << '\n';114 cout.precision(2);115 cout << "Total Worth: $" << total_val << '\n';116 cout.setf(orig, ios_base::floatfield);117 cout.precision(prec);118 }119120const stock &stock::topval(const stock &s) const {121if (s.total_val > total_val)122return s;123return *this;124 }125126 std::ostream &operator<<(std::ostream & os, const stock & s) { 127 os << "Company: " << pany128 << " Shares: " << s.shares << '\n';129 os << "Shares Prices: $" << s.share_val << '\n';130 os.precision(2);131 os << "Total Worth: $" << s.total_val << '\n';132 }133134135// run136137138139void ch12_3() {140using namespace std;141const int STKS = 4;142 stock ss[STKS] = {143 stock("NanoSmart", 12, 20.0),144 stock("Boffo Objects", 200, 2.0),145 stock("Monolithic Obelisks", 130, 3.25),146 stock("Fleep Enterprises", 60, 6.5)147 };148 cout << "Stock holdings: \n";149int st;150for (st = 0; st < STKS; ++ st)151 cout << ss[st];152const stock * top = &ss[0];153for (st = 1; st < STKS; ++ st)154 top = &top -> topval(ss[st]);155 cout << "\nMost valuable holding:\n";156 cout << *top;157 }1// chapter12_4_stack.h234 #ifndef LEARN_CPP_CHAPTER12_4_STACK_H5#define LEARN_CPP_CHAPTER12_4_STACK_H67 typedef unsigned long Item;89class Stack {10private:11enum {MAX = 10};12 Item * pitems;13int size;14int top;15public:16 Stack(int n = MAX);17 Stack(const Stack & st);18 ~Stack();19bool isempty() const;20bool isfull() const;21bool push(const Item & item);22bool pop(Item & item);23void show() const;24 Stack & operator=(const Stack & st);25 };2627282930#endif//LEARN_CPP_CHAPTER12_4_STACK_H3132// chapter12_4_stack.cpp3334 #include "chapter12_4_stack.h"35 #include <iostream>3637 Stack::Stack(int n) {38 pitems = new Item[n];39 size = n;40 top = 0;41 }4243 Stack::Stack(const Stack &st) {44 pitems = new Item[st.size];45 size = st.size;46 top = st.top;47for (int i = 0; i < st.top; ++ i)48 pitems[i] = st.pitems[i];49 }5051 Stack::~Stack() {52delete [] pitems;53 }5455bool Stack::isempty() const {56if (top == 0)57return true;58return false;59 }6061bool Stack::isfull() const {62if (top == size)63return true;64return false;65 }6667bool Stack::push(const Item &item) {68if (isfull())69return false;70 pitems[top ++] = item;71return true;72 }7374bool Stack::pop(Item &item) {75if (isempty())76return false;77 item = pitems[-- top];78return true;79 }8081 Stack &Stack::operator=(const Stack &st) { 82if (this == &st)83return *this;84if (pitems)85delete [] pitems;86 pitems = new Item[st.size];87 size = st.size;88 top = st.top;89for (int i = 0; i < st.top; ++ i)90 pitems[i] = st.pitems[i];91return *this;92 }9394void Stack::show() const {95using namespace std;96 cout << "Stack: ";97for (int i = 0; i < top; ++ i)98 cout << pitems[i] << "";99 cout << endl;100 }101102// run103104void ch12_4() {105 Stack s1(15);106 s1.show();107 s1.push(1234);s1.push(123);s1.push(12); 108 s1.show();109 Item t = 0;110 s1.pop(t);111 s1.show();112113 Stack s2(s1);114 s2.show();115 s2.push(12345);116 s2.show();117118 Stack s3 = s1;119 s3.show();120 s3.pop(t);121 s3.show();122 }// ch12_5&6// 待更新欢迎⼤家⼀起交流。

C++ primer plus第二章到第四章编程练习答案注：本人暑假正在看这本书，顺便就把题目做了，均经过了编译器通过，无注释。

第二章1：#include<iostream>#define max 10using namespace std;void main(){char name[max],dizhi[max];cout<<"请输入姓名: ";cin>>name;cout<<"请输入地址: ";cin>>dizhi;cout<<"姓名--->"<<name<<"\t地址--->"<<dizhi<<endl;}2：#include<iostream>using namespace std;void main(){long juli;cout<<"请输入距离long(1 long 为220码):";cin>>juli;cout<<"按照您输入的距离是:"<<juli*220<<"码"<<endl; }3：#include<iostream>using namespace std;void blind(){cout<<"Three blind mice\n";}void run(){cout<<"See how they run\n";}void main(){for(int i=0;i<2;i++)blind();for(int j=0;j<2;j++)run();}4：#include<iostream>using namespace std;void month(int age){cout<<"该年龄一共包含"<<age*12<<"个月！\n"; }void main(){int age;cout<<"请输入年龄:";cin>>age;month(age);}5：#include<iostream>using namespace std;double fahrenheit(double celsius){return 1.8*celsius+32.0;}void main(){double celsius;cout<<"please enter a celsius value:";cin>>celsius;cout<<celsius<<" degrees celsius is "<<fahrenheit(celsius)<<" degrees fahrenheit.\n";}6：#include<iostream>using namespace std;double astronomical(double light){return 63240*light;}void main(){double light;cout<<"Enter the number of light years:";cin>>light;cout<<light<<" light years = "<<astronomical(light)<<"astronomical units.\n";}7：#include<iostream>using namespace std;void display(int hours,int minutes){cout<<"Time: "<<hours<<":"<<minutes<<endl; }void main(){int hour,minute;cout<<"please input the time of hour:";cin>>hour;cout<<"please input the time of minute:";cin>>minute;display(hour,minute);}第三章1：#include<iostream>using namespace std;const float danwei=0.0833333;void iswap(int cun){cout<<"您的身高为: "<<cun*danwei<<" 英尺!"<<endl;}void main(){int cun;cout<<"请输入英寸单位的身高(整数):_______\b\b\b\b\b\b";cin>>cun;iswap(cun);}2：#include<iostream>using namespace std;const double yingchi=12;const double bang=2.2;const double memter=0.0245;void caculate(double chi,double cun,double weight){double BMI;double yingcun,mi,qianke;yingcun=cun+chi*yingchi;mi=yingcun*memter;qianke=weight/bang;BMI=qianke/(mi*mi);cout<<"您的BMI值为: "<<BMI<<endl;}void main(){double chi,cun,weight;cout<<"请输入身高(以几英尺几英寸方式输入): ";cin>>chi>>cun;cout<<"请输入体重(以磅为单位): ";cin>>weight;caculate(chi,cun,weight);}3：#include<iostream>using namespace std;void main(){double degrees,minutes,seconds,sum;cout<<"Enter a latitude in degrees,minutes,and seconds:"<<endl;cout<<"First,enter the degrees: ";cin>>degrees;cout<<"Next,enter the minutes of arc: ";cin>>minutes;cout<<"Finally,enter the seconds of arc: ";cin>>seconds;sum=degrees+minutes/60+seconds/3600;cout<<degrees<<" degrees,"<<minutes<<" minutes,"<<seconds<<" seconds= "<<sum<<" degrees."<<endl;}4：#include<iostream>using namespace std;const long m=60;const long h=60;const long d=24;int sumday(long seconds){long hour,minute;minute=seconds/m;hour=minute/h;return hour/d;}int sumhour(long seconds,int day){long minute;seconds=seconds-day*d*h*m;minute=seconds/m;return minute/h;}int summinute(long seconds,int day,int hour){seconds=seconds-(day*d*h*m+hour*h*m);return seconds/m;}int sumsecond(long seconds,int day,int hour,int minute){return seconds=seconds-(day*d*h*m+hour*h*m+minute*m); }void main(){long seconds;int day,hour,minute,second;cout<<"Enter the number of seconds: ";cin>>seconds;day=sumday(seconds);hour=sumhour(seconds,day);minute=summinute(seconds,day,hour);second=sumsecond(seconds,day,hour,minute);cout<<seconds<<" seconds = "<<day<<" days,"<<hour<<" hours,"<<minute<<" minutes,"<<second<<" seconds."<<endl;}5：#include<iostream>using namespace std;void main(){double world,us;cout<<"Enter the world's population: ";cin>>world;cout<<"Enter the population of the us: ";cin>>us;double bilv;bilv=us/world;cout<<"The population of the us is "<<bilv<<"% of the world population."<<endl;}6：#include<iostream>using namespace std;void main(){float memter,jialun;cout<<"以美国风格还是欧洲风格显示耗油量？m为美国，o 为欧洲!"<<endl;cout<<"请输入(m或o):";char c;cin>>c;if(c=='m'){cout<<"请输入驱车里程(英里):";cin>>memter;cout<<"请输入使用汽油量(加仑):";cin>>jialun;cout<<"汽车耗油量为:"<<memter/jialun<<"mpg."<<endl;}else{cout<<"请输入驱车里程(公里):";cin>>memter;cout<<"请输入使用汽油量(升):";cin>>jialun;float ofg;ofg=(100*jialun)/memter;cout<<"汽车耗油量为:"<<ofg<<"L/100Km."<<endl;}}7：include<iostream>using namespace std;void main(){cout<<"请输入欧洲风格的汽车耗油量(每100公里消耗的汽油量(升)):";float ofg;cin>>ofg;float jialun;jialun=ofg/3.875;float haoyou;haoyou=62.14/jialun;cout<<"转换成美国风格的耗油量(一加仑的里程，mpg):"<<haoyou<<"mpg."<<endl;}第四章1：#include<iostream>#include<cstring>const int num=10;using namespace std;int main(){cout<<"What's your first name?";char first[num];cin.getline(first,num);cout<<"whst's your last name?";char last[num];cin>>last;cout<<"what letter grade do you deserve?";char grade;cin>>grade;cout<<"what's your age?";int age;cin>>age;cout<<"-------------------------------------"<<endl;cout<<"Name: "<<last<<","<<first<<endl;cout<<"Grade: "<<char (grade+1)<<endl;cout<<"Age: "<<age<<endl;return 0;}2：#include<iostream>#include<string>using namespace std;int main(){string name,dessert;cout<<"Enter your name:\n";getline(cin,name);cin.get();cout<<"Enter your favorite dessert:\n";getline(cin,dessert);cout<<"I have some delicious "<<dessert<<" for you, "<<name<<".\n";return 0;}3：#include<iostream>#include<cstring>using namespace std;int main(){cout<<"Enter,your first name: ";char first[10];cin>>first;cout<<"Enter your last name: ";char last[10];cin>>last;strcat(last,", ");strcat(last,first);cout<<"Here's the information in a single string: "<<last<<endl;return 0;}4：include<iostream>#include<string>using namespace std;int main(){cout<<"Enter,your first name: ";string first;cin>>first;cout<<"Enter your last name: ";string last;cin>>last;last=last+", ";last=last+first;cout<<"Here's the information in a single string: "<<last<<endl;return 0;}5：#include<iostream>#include<string>using namespace std;struct CandyBar{char brand[20];double weight;long calories;};int main(){CandyBar snack={ "Mocha Munch",2.3,350 };cout<<snack.brand<<endl;cout<<snack.weight<<endl;cout<<snack.calories<<endl;return 0;}6：#include<iostream>#include<string>using namespace std;struct CandyBar{char brand[20];double weight;long calories;};int main(){CandyBar snack[3]={ { "Mocha Munch",2.3,350 },{ "caorui",3.6,456 },{ "denger",4.7,877 } };for(int i=0;i<3;i++){cout<<"-----------------------"<<endl;cout<<snack[i].brand<<endl;cout<<snack[i].weight<<endl;cout<<snack[i].calories<<endl;}cout<<"-----------------------"<<endl;return 0;}7：#include<iostream>#include<string>#include<cstring>using namespace std;struct pizza{string company;double diameter;double weight;};int main(){pizza p;cout<<"Please input the company of manufacture pizza: ";getline(cin,pany);cout<<"Please input the diameter of pizza: ";cin>>p.diameter;cout<<"Please input the weight of pizza: ";cin>>p.weight;cout<<"Name : "<<pany<<",and the company name is form of "<<pany.size()<<" words."<<endl;cout<<"Diameter: "<<p.diameter<<endl;cout<<"Weight: "<<p.weight<<endl;return 0;}8：#include<iostream>#include<string>#include<cstring>using namespace std;struct pizza{string company;double diameter;double weight;};int main(){pizza *p=new pizza;cout<<"Please input the diameter of pizza: ";cin>>p->diameter;cin.get();cout<<"Please input the company of manufacture pizza: ";getline(cin,p->company);cout<<"Please input the weight of pizza: ";cin>>p->weight;cout<<"Name : "<<p->company<<",and the company name is form of "<<p->company.size()<<" words."<<endl;cout<<"Diameter: "<<p->diameter<<endl;cout<<"Weight: "<<p->weight<<endl;return 0;}9：#include<iostream>#include<string>using namespace std;struct CandyBar{char brand[20];double weight;long calories;};int main(){CandyBar *snack=new CandyBar[3];strcpy(snack->brand,"shanghai");snack->weight=1.2;snack->calories=7;strcpy((snack+1)->brand,"beijing");(snack+1)->weight=2.3;(snack+1)->calories=8;strcpy((snack+2)->brand,"guangzhou");(snack+2)->weight=3.4;(snack+2)->calories=9;for(int i=0;i<3;i++){cout<<"-----------------------"<<endl;cout<<snack[i].brand<<endl;cout<<snack[i].weight<<endl;cout<<snack[i].calories<<endl;}cout<<"-----------------------"<<endl;return 0;}10：#include<iostream>#include<string>using namespace std;int main(){double grade[3];cout<<"Please input three grades of running."<<endl;for(int i=0;i<3;i++){cout<<"The "<<i+1<<" is :";cin>>grade[i];}cout<<"一共跑了3次,平均成绩为: "<<(grade[0]+grade[1]+grade[2])/3<<" 码."<<endl;return 0;}。

【C++PrimerPlus】编程练习答案——第16章 1// chapter16.h234 #ifndef LEARN_CPP_CHAPTER16_H5#define LEARN_CPP_CHAPTER16_H67 #include <iostream>8 #include <string>9 #include <cctype>10 #include <vector>11 #include <ctime>12 #include <cstdlib>13 #include <fstream>14 #include <algorithm>15 #include <queue>16 #include <list>17 #include <memory>1819void ch16_1();20void ch16_2();21void ch16_3();22int reduce(long * ar, int n);23void ch16_4();24 template<class T>25int reduce2(T * ar, int n);26void ch16_5();27bool newcustomer(double x);28void ch16_6();29 std::vector<int> lotto(int n, int select);30void ch16_7();31void ch16_8();32void ch16_9();3334struct Review {35 std::string title;36int rating;37 };38bool operator<(const Review & r1, const Review & r2);39bool worseThan(const Review & r1, const Review & r2);40bool FillReview(Review & rr);41void ShowReview(const std::shared_ptr <Review> & rr);42void ch16_10();4344#endif//LEARN_CPP_CHAPTER16_H1// chapter16.cpp234 #include "chapter16.h"56void ch16_1() {7using namespace std;8string str;9 cout << "input a string: ";10 getline(cin, str);11bool flag = true;12for (int i = 0; i < str.size() / 2; ++ i)13if (str[i] != str[str.size() - 1 - i]) {14 flag = false; break;15 }16 cout << (flag ? "yes!" : "no!") << endl;17 }1819void ch16_2() {20using namespace std;21string str;22 cout << "input a string: ";23 getline(cin, str);24bool flag = true;25for (int i = 0, j = str.size() - 1; i < j; ++ i, -- j) {26if (!isalpha(str[i]))27 ++i;28if (!isalpha(str[j]))29 --j;30if (i < j) {31 str[i] = tolower(str[i]);32 str[j] = tolower(str[j]);33if (str[i] != str[j]) {34 cout << str[i] << "" << str[j] << endl;35 flag = false;36break;37 }38 }39 }40 cout << (flag ? "yes!" : "no!") << endl;41 }4243void ch16_3() {44using namespace std;45const string FILENAME = "../C++PrimerPlus/testfiles/hangman.txt";46 ifstream InFile;47 InFile.open(FILENAME);48if (!InFile.is_open()) {49 cout << "file not found" << endl;50return;51 }52 vector<string> wordlist;53string t;54while (InFile >> t) {55 wordlist.push_back(t);56 t = "";57 }58 InFile.close();59 srand(time(0));60char play;61 cout << "Will you play a word game? <y/n> ";62 cin >> play;63 play = tolower(play);64while (play == 'y') {65string target = wordlist[rand() % wordlist.size()];66int length = target.length();67string attempt(length, '-');68string badchars;69int guesses = 6;70 cout << "Guess my secret word. It has " << length71 << " letters, and you guess\n"72 << "one letter at a time. You get " << guesses73 << " wrong guesses." << endl;74 cout << "Your word: " << attempt << endl;75while (guesses > 0 && attempt != target) {76char letter;77 cout << "Guess a letter: ";78 cin >> letter;79if (badchars.find(letter) != string::npos || attempt.find(letter) != string::npos) { 80 cout << "You already guessed that. Try again." << endl;81continue;82 }83int loc = target.find(letter);84if (loc == string::npos) {85 cout << "Oh, bad guess!" << endl;86 -- guesses;87 badchars += letter;88 }89else {90 cout << "Good guess!" << endl;91 attempt[loc] = letter;92 loc = target.find(letter, loc + 1);93while (loc != string::npos) {94 attempt[loc] = letter;95 loc = target.find(letter, loc + 1);96 }97 }98 cout << "Your word: " << attempt << endl;99if (attempt != target) {100if (badchars.length() > 0)101 cout << "Bad choices: " << badchars << endl;102 cout << guesses << " bad guesses left" << endl;103 }104 }105if (guesses > 0)106 cout << "That's right!" << endl;107else108 cout << "Sorry, the word is " << target << "." << endl;109 cout << "Will you play another? <y/n> ";110 cin >> play;111 play = tolower(play);112 }113 cout << "Bye! " << endl;114 }115116int reduce(long * ar, int n) {117 std::sort(ar, ar + n);118long * end = std::unique(ar, ar + n);119return int(end - ar);120 }121122void ch16_4() {123using namespace std;124long arr[5] = {3, 9, 0, 1, 1};125for (auto x : arr)126 cout << x << "\t";127 cout << endl;128int l = reduce(arr, 5);129for (int i = 0; i < l; ++ i)130 cout << arr[i] << "\t";131 cout << endl;132 }133134 template<class T>135int reduce2(T * ar, int n) {136 std::sort(ar, ar + n);137 T * end = std::unique(ar, ar + n);138return int(end - ar);139 }140141void ch16_5() {142using namespace std;143long arr[5] = {3, 9, 0, 1, 1};144for (auto x : arr)145 cout << x << "\t";146 cout << endl;147int l = reduce2(arr, 5);148for (int i = 0; i < l; ++ i)149 cout << arr[i] << "\t";150 cout << endl;151string arr2[5] = {"bb", "aa", "cc", "cc", "cc"};152for (auto x : arr2)153 cout << x << "\t";154 cout << endl;155int l2 = reduce2(arr2, 5);156for (int i = 0; i < l2; ++ i)157 cout << arr2[i] << "\t";158 cout << endl;159 }160161const int MIN_PER_HR = 60;162163bool newcustomer(double x) {164return (std::rand() * x / RAND_MAX < 1);165 }166167void ch16_6() {168// 懒得打字了，很简单。

Chapter 2 Programming ExercisesPE 2--‐1/*ProgrammingExercise2-1*/#include<stdio.h>intmain(void){printf("GustavMahler\n");printf("Gustav\nMahler\n");printf("Gustav");printf("Mahler\n");return0;}PE 2--‐3/*ProgrammingExercise2-3*/#include<stdio.h>intmain(void)PE 2--‐8/*ProgrammingExercise2-8*/#include<stdio.h>voidone_three(void);voidtwo(void);intmain(void){printf("startingnow:\n");one_three();printf("done!\n");return0;}voidone_three(void){printf("one\n");two();printf("three\n");}voidtwo(void){printf("two\n");}Chapter 3 Programming ExercisesPE 3--‐2/*ProgrammingExercise3-2*/#include<stdio.h>intmain(void){intascii;printf("EnteranASCIIcode:");scanf("%d",&ascii);printf("%distheASCIIcodefor%c.\n",ascii,ascii);return0;}"%s,%s\n",lname,fname);return0;}PE 4--‐4/*ProgrammingExercise4-4*/#include<stdio.h>intmain(void){floatheight;charname[40];printf("Enteryourheightininches:");scanf("%f",&height);printf("Enteryourname:");scanf("%s",name);printf("%s,youare%.3ffeettall\n",name,height/12.0);return0;}PE 4--‐7/*ProgrammingExercise4-7*/#include<stdio.h>#include<float.h>intmain(void){floatot_f=1.0/3.0;doubleot_d=1.0/3.0;printf("floatvalues:");printf("%.4f%.12f%.16f\n",ot_f,ot_f,ot_f);printf("doublevalues:"); printf("%.4f%.12f%.16f\n",ot_d,ot_d,ot_d);printf("FLT_DIG:%d\n ",FLT_DIG);printf("DBL_DIG:%d\n",DBL_DIG);return0;}Chapter 5 Programming ExercisesPE 5--‐1/*ProgrammingExercise5-1*/#include<stdio.h>intmain(void){constintminperhour=60;intminutes,hours,intmain(void)/*findssumoffirstnintegers*/{intcount,sum;intn;printf("Entertheupperlimit:");scanf("%d",&n);count=0;sum=0;while(count++<n)sum=sum+count;printf("sum=%d\n",sum);return0;}PE 5--‐7/*ProgrammingExercise5-7*/#include<stdio.h>voidshowCube(doublex);intmain(void)/*findscubeofenterednumber*/ {doubleval;printf("Enterafloating-pointvalue:");scanf("%lf",&val);showCube(val);return0;}voidshowCube(doublex){printf("Thecubeof%eis%e.\n",x,x*x*x);}Chapter 6 Programming ExercisesPE 6--‐1/*pe6-1.c*//*thisimplementationassumesthecharactercodes*//*aresequential,astheyareinASCII.*/#include<stdio.h>#defineSIZE26intmain(void){charlcase[SIZE];inti;for(i=0;i<SIZE;i++)lPE 6--‐8/*pe6-8.c*/#include<stdio.h>intmain(void){doublen,m;doubleres;printf("Enterapairofnumbers:");while(scanf("%lf%lf",&n,&m)==2){res=(n-m)/(n*m);printf("(%.3g-%.3g)/(%.3g*%.3g)=%.5g\n",n,m,n,m,res);printf("Enternextpair(non-numerictoquit):");}return0;}PE 6--‐11/*pe6-11.c*/#include<stdio.h>#defineSIZE8intmain(void){intvals[SIZE];inti;printf("Pleaseenter%dintegers.\n",SIZE);for(i=0;i<SIZE;i++)scanf("%d",&vals[i]);printf("Here,inreverseorder,arethevaluesyouentered:\n");for(i=SIZE-1;i>=0;i--)printf("%d",vals[i]);printf("\n");return0;}PE 6--‐13/*pe6-13.c*/}for(i=0;i<SIZE;i++)printf("%8g",arr[i]);printf("\n");for(i=0;i<SIZE;i++)printf("%8g",arr_cumul[i]);printf("\n");return0;}PE 6--‐16/*pe6-16.c*/#include<stdio.h>#defineRATE_SIMP0.10#defineRATE_COMP0.05#defineINIT_AMT100.0intmain(void){doubledaphne=INIT_AMT;doubledeidre=INIT_AMT;intyears=0;while(deidre<=daphne){daphne+=RATE_SIMP*INIT_AMT;deidre+=RATE_COMP*deidre;++years;}printf("Investmentvaluesafter%dyears:\n",years);printf("Daphne:$%.2f\n", daphne);printf("Deidre:$%.2f\n",deidre);return0;}Chapter 7 Programming ExercisesPE 7--‐1/*ProgrammingExercise7-1*/#include<stdio.h>intmain(void){charch;intsp_ct=0;intnl_ct=0;intother=0;while((ch=getchar())printf("Numberofodds:%d",ct_odd);if(ct_odd>0)printf("average:%g",sumodd/ct_odd);putchar('\n');printf("\ndone\n");return0;}PE 7--‐5/*ProgrammingExercise7-5*/#include<stdio.h>intmain(void){charch;intct1=0;intct2=0;while((ch=getchar())!='#'){switch(ch){case'.':putchar('!');++ct1;break;case'!':putchar('!');putchar('!');++ct2;break;default:putchar(ch);}}printf("%dreplacement(s)of.with!\n",ct1);printf("%dreplacement(s)of!with!!\n",ct2);return0;}PE 7--‐7//ProgrammingExercise7-7#include<stdio.h>#defineBASEPAY10//$10perhour#defineBASEHRS40//hoursatbasepay#defineOVERTIME1.5//1.5time{if(limit>1)printf("Herearetheprimenumbersupthrough%d\n",limit);elseprintf("Noprimes.\n");for(num=2;num<=limit;num++){for(div=2,numIsPrime=true;(div*div)<=num;div++)if(num%div==0)numIsPrime=false;if(numIsPrime)printf("%disprime.\n",num);}printf("Enterapositiveinteger(qtoquit):");}printf("Done!\n");return0;}PE 7--‐11/*pe7-11.c*//*ProgrammingExercise7-11*/#include<stdio.h>#include<ctype.h>intmain(void){constdoubleprice_artichokes=2.05;constdoubleprice_beets=1.15;constdoubleprice_carrots=1.09;constdoubleDISCOUNT_RATE=0.05;constdoubleunder5=6.50;constdoubleunder20=14.00;constdoublebase20=14.00;constdoubleextralb=0.50;charch;doublelb_artichokes=0;doublelb_beets=}final_total=cost_total+shipping-discount;printf("Yourorder:\n");printf("%.2flbsofartichokesat$%.2fperpound:$%.2f\n",lb_artichokes,price_artic hokes,cost_artichokes);printf("%.2flbsofbeetsat$%.2fperpound:$%.2f\n",lb_bee ts,price_beets,cost_beets);printf("%.2flbsofcarrotsat$%.2fperpound:$%.2f\n",lb _carrots,price_carrots,cost_carrots);printf("Totalcostofvegetables:$%.2f\n",cost_total);if(cost_total>100)printf("V olumediscount:$%.2f\n",discount);printf("Shipping:$%.2f\n",shipping);printf("Totalcharges:$%.2f\n",final_total);return0;}Chapter 8 Programming ExercisesPE 8--‐1/*ProgrammingExercise8-1*/#include<stdio.h>intmain(void){intch;intct=0;while((ch=getchar())!=EOF)ct++;printf("%dcharactersread\n",ct);return0;}PE 8--‐3/*ProgrammingExercise8-3*//*Usingctype.heliminatesneedtoassumeconsecutivecoding*/ #include<stdio.h>#include<ctype.h>intmain(void){intch;unsignedlonguct=0;unsignedlonglct=0;unsignedlongoct=0;while((ch=getchar())!=EOF)if(isupper(ch))uct++;elseif(islower(ch))lct++;elseoct++;}1;elseif(response=='l')low=guess+1;guess=(high+low)/2;printf("Well,then,isit%d?\n",guess);}printf("IknewIcoulddoit!\n");return0;}PE 8--‐7/*ProgrammingExercise8-7*/#include<stdio.h>#include<ctype.h>#include<stdio.h>#defineBASEPAY18.75//$8.75perhour#defineBASEPAY29.33//$9.33perhour#defineBASEPAY310.00//$10.00perhour#defineBASEPAY411.20//$11.20perhour#defineBASEHRS40//hoursatbasepay#defineOVERTIME1.5//1.5time#defineAMT1300//1stratetier#defineAMT2150//2stratetier#defineRATE10.15//ratefor1sttier#defineRATE20.20//ratefor2ndtier#defineRATE30.25//ratefor3rdtierintgetfirst(void);voidmenu(void);intmain(void){doublehours;doublegross;doublenet;doubletaxes;doublepay;charresponse;menu();printf("a)$%4.2f/hrb)$%4.2f/hr\n",BASEPAY1,BASEPAY2);printf("c)$%5.2f/hrd)$%5.2f/hr\n",BASEPAY3,BASEPAY4);printf("q)quit\n");printf("********************************************************""*********\n");}intgetfirst(void){intch;ch=getchar();while(isspace(ch))ch=getchar();while(getchar()!='\n')continue;returnch;}Chapter 9 Programming ExercisesPE 9--‐1/*ProgrammingExercise9-1*/#include<stdio.h>doublemin(double,double);intmain(void){doublex,y;printf("Entertwonumbers(qtoquit):");while(scanf("%lf%lf",&x,&y)==2){printf("Thesmallernumberis%f.\n",min(x,y));printf("Nexttwovalues(qtoquit):");}printf("Bye!\n");return0;}doublemin(doublea,doubleb){for(col=0;col<c;col++)putchar(ch);putchar('\n');}return;}PE 9--‐5/*ProgrammingExercise9-5*/#include<stdio.h>voidlarger_of(double*p1,double*p2);intmain(void){doublex,y;printf("Entertwonumbers(qtoquit):");while(scanf("%lf%lf",&x,&y)==2){larger_of(&x,&y);}printf("Bye!\n");return0;}voidlarger_of(double*p1,double*p2){if(*p1>*p2)*p2=*p1;else*p1=*p2;}//alternatively:/*voidlarger_of(double*p1,double*p2){*p1=*p2=*p1>*p2?*p1:*p2;*/printf("baseshouldbeintherange2-10:");}if(count!=1)break;printf("Base%dequivalent:",b);to_base_n(number,b);putchar('\n');printf("Enteraninteger(qtoquit):\n");}printf("Done.\n");return0;}voidto_base_n(intx,intbase)/*recursivefunction*/ {intr;r=x%base;if(x>=base)to_base_n(x/base,base);putchar('0'+r);return;}Chapter 10 Programming Exercises/*ProgrammingExercise10-1*/#include<stdio.h>#defineMONTHS12//numberofmonthsinayear#defineYRS5//numberofyearsofdataintmain(void){//initializingrainfalldatafor2010-2014constfloatrain[YRS][MONTHS]={{4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},{8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},{9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},{7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},{7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}};intyear,month;floatsubtot,total;RS;year++)}intmax_arr(constintar[],intn){inti;intmax=ar[0];/*don'tuse0asinitialmaxvalue--failsifallarrayvaluesareneg*/ for(i=1;i<n;i++)if(max<ar[i])max=ar[i];returnmax;}voidshow_arr(constintar[],intn){inti;for(i=0;i<n;i++)printf("%d",ar[i]);putchar('\n');}PE 10--‐5/*ProgrammingExercise10-5*/#defineLEN10doublemax_diff(constdoublear[],intn);voidshow_arr(constdoublear[],intn);intmain(void){doubleorig[LEN]={1.1,2,3,4,12,61.3,7,8,9,10};doublemax; show_arr(orig,LEN);max=max_diff(orig,LEN);printf("%g=maximumdifference\n",max);return0;}doublemax_diff(constdoublear[],intn) {inti;doublemax=ar[0];doublemin=ar}}{inti;for(i=0;i<n;i++)printf("%d",ar[i]);putchar('\n');}PE 10--‐11/*ProgrammingExercise10-11*/#include<stdio.h>#defineROWS3#defineCOLS5voidtimes2(intar[][COLS],intr);voidshowarr2(intar[][COLS],intr);intmain(void){intstuff[ROWS][COLS]={{1,2,3,4,5},{6,7,8,-2,10},{11,12,13,14,15}};showarr2(stuff,ROWS);putchar('\n');times2(stuff,ROWS);showarr2(stuff,ROWS);return0;}voidtimes2(intar[][COLS],intr){introw,col;for(row=0;row<r;row++)for(col=0;col<COLS;col++)ar[row][col]*=2;}voidshowarr2(intar[][COLS],intr){introw,col;for(i=0;i<n;i++){printf("Entervalue#%d:",i+1);scanf("%lf",&ar[i]);}}doubleaverage2d(introws,intcols,doublear[rows][cols]){intr,c;doublesum=0.0;for(r=0;r<rows;r++)for(c=0;c<cols;c++)sum+=ar[r][c];if(rows*cols>0)returnsum/(rows*cols);elsereturn0.0;}doublemax2d(introws,intcols,doublear[rows][cols]){intr,c;doublemax=ar[0][0];for(r=0;r<rows;r++)for(c=0;c<cols;c++)if(max<ar[r][c])max=ar[r][c];returnmax;}voidshowarr2(introws,intcols,doublear[rows][cols]){introw,col;for(row=0;row<rows;row++){for(col=0;col<cols;col++)printf("%g",ar[row][col]);putchar('\n');}}doubleaverage(constdoublear[],intn) {inti;doublesum=0.0;}char*getword(char*str){intch;char*orig=str;//skipoverinitialwhitespacewhile((ch=getchar ())!=EOF&&isspace(ch))continue;if(ch==EOF)returnNULL;else*str++=ch;//firstcharacterinword//getrestofwordwhile((ch=getchar())!=EOF&&!isspace(ch))*str++=ch;*str='\0';if(ch==EOF)returnNULL;else{while(ch!='\n')ch=getchar();returnorig;}}PE 11--‐6#include<stdio.h>#include<string.h>#defineLEN80_Boolis_within(constchar*str,charc);char*s_gets(char*st,intn);intmain(void){charinput[LEN];charch;intfound;;printf("Enterastring:");while(s_gets(input,LEN)&&input[0]!='\0'){printf("Enteracharacter:");ch=getchar();while(getchar()!='\n')continue;found=is_within(input,ch);if(found==0)printf("%cnotfoundinstring.\n",ch);elseputs("Notfound");return0;}#include<string.h>char*string_in(constchar*s1,constchar*s2){intl2=strlen(s2);inttries;/*maximumnumberofcomparisons*/intnomatch=1;/*setto0ifmatchisfound*/ tries=strlen(s1)+1-l2;if(tries>0)while((nomatch=strncmp(s1,s2,l2))&&tries--)s1++;if(nomatch)returnNULL;elsereturn(char*)s1;/*castconstaway*/PE 11--‐10/*ProgrammingExercise11-10*/#include<stdio.h>#include<string.h>//forstrchr();#defineLEN81intdrop_space(char*s);char*s_gets(char*st,intn);intmain(void){charorig[LEN];puts("Enterastringof80charactersorless:");while(s_gets(orig,LEN)&&orig[0]!='\0'){drop_space(orig);puts(orig);puts("Enternextstring(orjustEntertoquit):");}}#include<stdbool.h>//forbool,true,falseintmain(void){charc;//readincharacterintlow_ct=0;//numberoflowercasecharactersintup_ct=0;//numberofuppercasecharactersintdig_ct=0;//numberofdigitsintn_words=0;//numberofwordsintpunc_ct=0;//numberofpunctuationmarksboolinword=false;//==trueifcisinaword printf("Entertexttobeanalyzed(EOFtoterminate):\n");while((c=getchar())!=EOF) {if(islower(c))low_ct++;elseif(isupper(c))up_ct++;elseif(isdigit(c))dig_ct++;elseif(ispunct(c))punc_ct++;if(!isspace(c)&&!inword){inword=true;//startinganewwordn_words++;//countwordif(isspace(c)&&inword)inword=false;//reachedendofword}printf("\nwords=%d,lowercase=%d,uppercase=%d," "digits=%d,punctuation=%d\n",n_words,low_ct,up_ct,dig_ct,punc_ct);return0;}PE 11--‐14/*ProgrammingExercise11-14*/#include<stdio.h>#include<stdlib.h>/*foratof()*/#include<math.h>/*forpow()*/intmain(intargc,char*argv[])}}if(ok)while((ch=getchar())!=EOF){switch(mode){case'p':putchar(ch);break;case'u':putchar(toupper(ch));break;case'l':putchar(tolower(ch));}}return0;Chapter 12 Programming ExercisesPE 12--‐1/*pe12-1.c--deglobalizingglobal.c*//*ProgrammingExercise12-1*//*oneofseveralapproaches*/#include<stdio.h>voidcritic(int*u);intmain(void){intunits;/*unitsnowlocal*/printf("Howmanypoundstoafirkinofbutter?\n");scanf("%d",&units);while(units!=56)critic(&units);printf("Youmusthavelookeditup!\n");return0;}{if(*pm!=METRIC&&*pm!=US){printf("Invalidmodespecified.Mode%d\n",*pm);printf("Previousmodewil lbeused.\n");*pm=USE_RECENT;}}voidget_info(intmode,double*pd,double*pf){if(mode==METRIC)printf("Enterdistancetraveledinkilometers:");elseprintf("Enterdistancetraveledinmiles:");scanf("%lf",pd);if(mode==Mprintf("Enterfuelconsumedinliters:");elseprintf("Enterfuelconsumedingallons:");scanf("%lf",pf);}voidshow_info(intmode,doubledistance,doublefuel){printf("Fuelconsumptionis");if(mode==METRIC)printf("%.2flitersper100km.\n",100*fuel/distance);elseprintf("%.1fmilespergallon.\n",distance/fuel);}//pe12-3b.c//compilewithpe12-3a.c#include<stdio.h>#include"pe12-3a.h"intmain(void)for(search=top+1;search<limit;search++)if(array[search]>array[top]){temp=array[search];array[search]=array[top];array[top]=temp;}}/*print.c--printsanarray*/voidprint(constintarray[],intlimit){intindex;for(index=0;index<limit;index++){printf("%2d",array[index]);if(index%10==9)putchar('\n');}if(index%10!=0)//iflastlinenotcompleteputchar('\n');}PE 12--‐7/*pe12-7.c*/#include<stdio.h>#include<stdlib.h>/*forsrand()*/#include<time.h>/*fortime()*/introllem(int);intmain(void){intdice,count,roll;intsides;intset,sets;srand((unsignedint)time(0));/*randomizerand()*/ printf("Enterthenumberofsets;enterqtostop:");while(scanf("%d",&sets)==1)}printf("Usage:%ssourcefiletargetfile\n",argv[0]);exit(EXIT_FAILURE);}if((source=fopen(argv[1],"rb"))==NULL){printf("Couldnotopenfile%sforinput\n",argv[1]);exit(EXIT_FAILURE);}if((target=fopen(argv[2],"wb"))==NULL){printf("Couldnotopenfile%sforoutput\n",argv[2]);exit(EXIT_FAILURE);}while((byte=getc(source))!=EOF){putc(byte,target);}if(fclose(source)!=0)printf("Couldnotclosefile%s\n",argv[1]);if(fclose(target)!=0)printf("Couldnotclosefile%s\n",argv[2]);return0;}PE 13--‐4/*ProgrammingExercise13-4*/#include<stdio.h>#include<stdlib.h>intmain(intargc,char*argv[]){intbyte;FILE*source;intfilect;}FILE*fa,*fs;intfiles=0;intfct;if(argc<3){printf("Usage:%sappendfilesourcefile[s]\n",argv[0]);exit(EXIT_FAILURE);}if((fa=fopen(argv[1],"a"))==NULL){fprintf(stderr,"Can'topen%s\n",argv[1]);exit(EXIT_FAILURE);}if(setvbuf(fa,NULL,_IOFBF,BUFSIZE)!=0){fputs("Can'tcreateoutputbuffer\n",stderr);exit(EXIT_FAILURE);}for(fct=2;fct<argc;fct++){if(strcmp(argv[fct],argv[1])==0)fputs("Can'tappendfiletoitself\n",stderr);els eif((fs=fopen(argv[fct],"r"))==NULL)fprintf(stderr,"Can'topen%s\n",argv[fct]);else{if(setvbuf(fs,NULL,_IOFBF,BUFSIZE)!=0){fputs("Can'tcreateoutputbuffer\n",stderr);continue;}append(fs,fa);if(ferror(fs)!=0)fprintf(stderr,"Errorinreadingfile%s.\n",argv[fct]);if(ferror(fa)!=0)fprintf(stderr,"Errorinwritingfile%s.\n",argv[1]);fclose(fs);files++;printf("File%sappended.\n",argv[fct]);}}printf("Done.%dfilesappended.\n",files);fclose(fa);return0;}{while(ch1!=EOF&&ch1!='\n')/*skippedafterEOFreached*/ {putchar(ch1);ch1=getc(f1);}if(ch1!=EOF){putchar('\n');ch1=getc(f1);}while(ch2!=EOF&&ch2!='\n')/*skippedafterEOFreached*/ {putchar(ch2);ch2=getc(f2);}if(ch2!=EOF){putchar('\n');ch2=getc(f2);}}if(fclose(f1)!=0)printf("Couldnotclosefile%s\n",argv[1]);if(fclose(f2)!=0)printf("Couldnotclosefile%s\n",argv[2]);return0;}/*ProgrammingExercise13-7b*//*codeassumesthatend-of-lineimmediatelyprecedesend-of-file*/#include<stdio.h>#include<stdlib.h>intmain(intargc,char*argv[]){intch1,ch2;FILE*f1;}putchar('\n');ch2=getc(f2);}}if(fclose(f1)!=0)printf("Couldnotclosefile%s\n",argv[1]);if(fclose(f2)!=0)printf("Couldnotclosefile%s\n",argv[2]);return0;}PE 13--‐9/*ProgrammingExercise13-9*//*tosimplifyaccounting,storesonenumberandwordperline*/#include<stdio.h>#include<stdlib.h>#defineMAX47intmain(void){FILE*fp;charwords[MAX];intwordct=0;if((fp=fopen("wordy","a+"))==NULL){fprintf(stderr,"Can'topen\"words\"file.\n");exit(EXIT_FAILURE);}//determinecurrentnumberoflinesrewind(fp);while(fgets(words,MAX,fp)!=NULL)wordct++;rewind(fp);puts("Enterwordstoaddtothe file;pressthe#");puts("keyatthebeginningofalinetoterminate.");while((fscanf(stdin,"%40s ",words)==1)&&(words[0]!='#'))fprintf(fp,"%3d:%s\n",++wordct,words);puts("Filecontents:");}return0;}PE 13--‐12: Sample Input Text009000000000589985200000000000000090000000589985520000000000000000000000581985452000000000000090000000589985045200000000009000000000589985004520000000000000000000589185000452000000000000000000589985000045200000555555555555589985555555555555888888888888589985888888888888999909999999999999999939999999888888888888589985888888888888555555555555589985555555555555000000000000589985000000000000000000000000589985000066000000000022000000589985005600650000000033000000589985056111165000000044000000589985005600650000000055000000589985000066000000000000000000589985000000000000000000000000589985000000000000PE 13--‐12/*ProgrammingExercise13-12*/#include<stdio.h>}voidinit(chararr[][COLS],charch){intr,c;for(r=0;r<ROWS;r++)for(c=0;c<COLS;c++)arr[r][c]=ch;}voidMakePic(intdata[][COLS],charpic[][COLS],introws) {introw,col;for(row=0;row<rows;row++)for(col=0;col<COLS;col++)pic[row][col]=trans[data[row][col]];}Chapter 14 Programming ExercisesPE 14--‐1/*pe14-1.c*/#include<stdio.h>#include<string.h>#include<ctype.h>structmonth{charname[10];charabbrev[4];intdays;intmonumb;};conststructmonthmonths[12]={{"January","Jan",31,1},{"February","Feb",28,2},{"March","Mar",31,3},{"April","Apr",30,4},{"May","May",31,5},{"June","Jun",30,6},{"July","Jul",31,7},{"August","Aug",31,8},}char*s_gets(char*st,intn);#defineMAXTITL40#defineMAXAUTL40#defineMAXBKS100/*maximumnumberofbooks*/structbook{/*setupbooktem plate*/chartitle[MAXTITL];charauthor[MAXAUTL];floatvalue;};voidsortt(structbook*pb[],intn);voidsortv(structbook*pb[],intn);intmain(void){structbooklibrary[MAXBKS];/*arrayofbookstructures*/structbook*pbk[MAXB KS];/*pointersforsorting*/intcount=0;intindex;printf("Pleaseenterthebooktitle.\n");printf("Press[enter]atthestartofalinetostop.\n");while(count<MAXBKS&&s_gets(library[count].title,MAXTITL)!=NULL&&library[count].title[0]!='\0'){printf("Nowentertheauthor.\n");s_gets(library[count].author,MAXAUTL);printf("Nowenterthevalue.\n");scanf("%f",&library[count].value);pbk[count]=&library[count];count++;while(getchar()!='\n')continue;/*clearinputline*/if(count<MAXBKS)printf("Enterthenexttitle.\n");}printf("Hereisthelistofyourbooks:\n");for(index=0;index<count;index++)printf("%sby%s:$%.2f\n",library[index].title,library[index].author,library[index].value);}}}char*s_gets(char*st,intn){char*ret_val;char*find;ret_val=fgets(st,n,stdin);if(ret_val){find=strchr(st,'\n');//lookfornewlineif(find)//iftheaddressisnotNULL,*find='\0';//placeanullcharacterthereelsewhile(getchar()!='\n')continue;//disposeofrestofline}returnret_val;}PE 14--‐5/*pe14-5.c*/#include<stdio.h>#include<string.h>#defineLEN14#defineCSIZE4#defineSCORES3structname{charfirst[LEN];charlast[LEN];};structstudent{structnameperson;floatscores[SCORES];floatmean;};voidget_scores(structstudentar[],intlim);voidfind_means(structstude ntar[],intlim);voidshow_class(conststructstudentar[],intlim);voidsho w_ave(conststructstudentar[],intlim);intmain(void) {structstudentclass[CSIZE]={{"Flip","Snide"},}}voidshow_class(conststructstudentar[],intlim) {inti,j;charwholename[2*LEN];for(i=0;i<lim;i++){strcpy(wholename,ar[i].person.first);strcat(wholename,"");strcat( wholename,ar[i]st);printf("%27s:",wholename);for(j=0;j<SCORES;j++)printf("%6.1f",ar[i].scores[j]);printf("Average=%5.2f\n",ar[i].mean);}}voidshow_ave(conststructstudentar[],intlim) {inti,j;floattotal;printf("\n%27s:","QUIZA VERAGES");for(j=0;j<SCORES;j++){for(total=0,i=0;i<lim;i++)total+=ar[i].scores[j];printf("%6.2f",total/lim);}for(total=0,i=0;i<lim;i++)total+=ar[i].mean;printf("All=%5.2f\n",total/lim);}PE 14--‐7/*pe14-7.c*/#include<stdio.h>#include<stdlib.h>#include<string.h>{if(count==0)puts("Currentcontentsofbook.dat:");printf("%sby%s:$%.2f\n",library[count].book.title,librar y[count].book.author,library[count].book.value);printf("Doyouwishtochangeordeletethisentry?<y/n>");if(getlet("yn")=='y'){printf("Enterctochange,dtodeleteentry:");if(getlet("cd")=='d'){library[count].delete_me=true;deleted++;puts("Entrymarkedfordeletion.");}elseupdate(&library[count]);}count++;}fclose(pbooks);}filecount=count-deleted;if(count==MAXBKS){fputs("Thebook.datfileisfull.",stderr);exit(EXIT_FAILURE);}puts("Pleaseaddnewbooktitles.");puts("Press[enter]atthestartofalinetostop.");open=0;while(filecount<MAXBKS){if(filecount<count){while(library[open].delete_me==false)open++;}}{intstatus=CONTINUE;if(s_gets(pb->book.title,MAXTITL)==NULL||pb->book.title[0]=='\0')status=DONE;else{printf("Nowentertheauthor:");s_gets(pb->book.author,MAXAUTL);printf("Nowenterthevalue:");while(scanf("%f",&pb->book.value)!=1){puts("Pleaseusenumericinput");scanf("%*s");}while(getchar()!='\n')continue;/*clearinputline*/pb->delete_me=false;}returnstatus;}voidupdate(structpack*item){structbookcopy;charc;copy=item->book;puts("Entertheletterthatindicatesyourchoice:");puts("t)modifytitlea)modifya uthor");puts("v)modifyvalues)quit,savingchanges");puts("q)quit,ignorechanges");while((c=getlet("tavsq"))!='s'&&c!='q'){switch(c){case't':puts("Enternewtitle:");s_gets(copy.title,MAXTITL);break; case'a':puts("Enternewauthor:");s_gets(copy.author,MAXAUTL);break;case'v:puts("Enternewvalue:");while(scanf("%f",&copy.value)!=1)#defineEMPTY0#defineTAKEN1#defineCONTINUE1#defineDONE0 structplanestats{intseat_id;intstatus;charlast[LEN];charfirst[LEN];};intgetmenu(void);intgetlet(constchar*);intopenings(conststructplanestats[],int);voidshow_empties(conststructpl anestats[],int);voidlist_assign(structplanestats*[],int);voidassign_seat(str uctplanestats[],int);voiddelete_seat(structplanestats[],int);voidshow_seats(conststructplanestats[],int);voidsort(structplanestats*[],int);voidmakeli st(conststructplanestats[],char*,int);char*s_gets(char*st,intn);。

CPrimerPlus第七章编程练习参考答案#includeint main(void){char ch;int sp_ct, nl_ct, other;sp_ct = nl_ct = other = 0;while ((ch = getchar()) != '#'){if (ch == ' ')sp_ct++;else if (ch == '\n')nl_ct++;elseother++;}printf("%d whitespace, %d newline, %d other.\n", sp_ct, nl_ct, other);return 0;}#includeint main(void){char ch;int count = 0;while ((ch = getchar()) != '#') {if (ch == '\n')continue;count ++;putchar(ch);printf("/%d ", ch);if (count % 8 == 0)printf("\n");}printf("That's all!");return 0;}#includeint main(void){int num;int e_ct, o_ct;double e_sum, o_sum;e_ct = o_ct = 0;e_sum = o_sum = 0.0;printf("Enter the integer:(0 to quit).\n");while (scanf("%d", &num) == 1 && num != 0) { if (num % 2 == 0){e_ct++;e_sum += num;}else{o_ct++;o_sum += num;}printf("Enter next integer:(0 to quit).\n");}printf("%d even entered.", e_ct);if (e_ct > 0)printf(" Average is %g.", e_sum / e_ct); putchar('\n');printf("%d odd entered.", o_ct);if (o_ct > 0)printf(" Average is %g.", o_sum / o_ct); putchar('\n');printf("Done!\n");return 0;}/* programming exercise 7-4 */#include#define ECM '!'int main(void){char ch;int fs_ct = 0;int em_ct = 0;while ((ch = getchar()) != '#'){if (ch == '.'){putchar(ECM);fs_ct++;}else if (ch == '!'){putchar(ECM);putchar(ECM);em_ct++;}elseputchar(ch);}printf("%d times fs to em, %d times em to double em.\n", fs_ct, em_ct);return 0;}/* programming exercise 7-5 */#includeint main(void){int num;int e_ct = 0, o_ct = 0;double e_sum = 0.0, o_sum = 0.0;printf("Enter the integer:(0 to quit).\n");while (scanf("%d", &num) == 1 && num != 0) {switch(num % 2){case 0:e_ct++;e_sum += num;break;case 1:o_ct++;o_sum += num;break;}printf("Enter next integer:(0 to quit).\n");}printf("%d even entered.", e_ct);if (e_ct > 0)printf(" Average is %g.", e_sum / e_ct); putchar('\n');printf("%d odd entered.", o_ct);if (o_ct > 0)printf(" Average is %g.", o_sum / o_ct); putchar('\n');printf("Done!\n");return 0;}/* programming exercise 7-6 */#includeint main(void){char ch;char prev = 0;/* 记得对prev进行0填充，否则有可能定义的内存的垃圾数据恰好为e */ int count = 0;while ((ch = getchar()) != '#'){if (ch == 'i' && prev == 'e')count++;prev = ch;}switch (count){case 0:printf("\"ei\" no apeared.\n");break;case 1:printf("\"ei\" apeared 1 time.\n");break;default:printf("\"ei\" apeared %d times", count);}return 0;}/* programming exercise 7-7 */#include#define BASEPAY 10#define BASEHRS 40#define OVERRATE 1.5#define LEVEL1 300#define LEVEL2 150#define TAX1 0.15#define TAX2 0.20#define TAX3 0.25int main(void){float hours;float total, tax, net;printf("Please enter your work time: ");scanf("%f", &hours);if (hours > BASEHRS)total = BASEPAY * (BASEHRS + (hours - BASEHRS) * OVERRATE);elsetotal = hours * BASEPAY;if (total <= LEVEL1)tax = total * TAX1;else if (total <= (LEVEL1 + LEVEL2))tax = LEVEL1 * TAX1 + (total - LEVEL1) * TAX2;elsetax = LEVEL1 * TAX1 + LEVEL2 * TAX2 + (total - LEVEL1 - LEVEL2) * TAX3;net = total - tax;printf("total = %g, tax = %g, net = %g.\n",total, tax, net);return 0;}/* programming exercise 7-8 */#include#define BASEHRS 40#define OVERRATE 1.5#define T_LEVEL1 300#define T_LEVEL2 150#define S_LEVEL1 8.75#define S_LEVEL2 9.33#define S_LEVEL3 10.00#define S_LEVEL4 11.20#define TAX1 0.15#define TAX2 0.20#define TAX3 0.25int main(void){float hours;float basepay;float total, tax, net;int choice;printf("****************************************************** ***********\n");printf("Enter the number corresponding to the desired pay rate or action:\n");printf("1)$8.75/hr 2)$9.33/hr\n");printf("3)$10.00/hr 4)$11.20/hr\n");printf("5)quit\n");printf("****************************************************** ***********\n");while (scanf("%d", &choice) == 1 && choice != 5){switch(choice){case 1:basepay = S_LEVEL1;break;case 2:basepay = S_LEVEL2;break;case 3:basepay = S_LEVEL3;break;case 4:basepay = S_LEVEL4;break;default:printf("You should enter the number between 1 to 4 (5 to quit).\n");printf("Please enter the right number: \n");continue;}printf("Please enter your work time: ");scanf("%f", &hours);if (hours > BASEHRS)total = basepay * (BASEHRS + (hours - BASEHRS) * OVERRATE);elsetotal = hours * basepay;if (total <= T_LEVEL1)tax = total * TAX1;else if (total <= (T_LEVEL1 + T_LEVEL2))tax = T_LEVEL1 * TAX1 + (total - T_LEVEL1) * TAX2;elsetax = T_LEVEL1 * TAX1 + T_LEVEL2 * TAX2 + (total - T_LEVEL1 - T_LEVEL2) * TAX3;net = total - tax;printf("total = %g, tax = %g, net = %g.\n",total, tax, net);printf("Please enter next number:\n");}printf("That's all!\n");return 0;}/* programmming exercise 7-9 */#includeint main(void){int num;int div;int count;printf("Please enter the limit in integer:\n"); scanf("%d", &num);while (num >1){for (div = 2, count = 0; div <= num / 2; div++) {if(num % div == 0)count++;}if (count == 0)printf("%d ", num);num--;}printf("\nThat's all!\n");return 0;}/* programming exercise 7-10 */#include#define RATE1 0.15#define RATE2 0.28#define LEVEL1 17850#define LEVEL2 23900#define LEVEL3 29750#define LEVEL4 14875int main(void){double tax;double income;int type;long level;printf("Please choose your type as follow:(q to quit)\n"); printf("1)Single; 2)Householder;\n");printf("3)Married; 4)Divorced\n");while (scanf("%d", &type) == 1){switch (type){case 1:level = LEVEL1;break;case 2:level = LEVEL2;break;case 3:level = LEVEL3;break;case 4:level = LEVEL4;break;default:printf("You should choose the number""between 2 and 4(q to quit).\n");printf("Please enter the right number:\n"); continue;}printf("Please enter your income:\n");scanf("%lf", &income);if (income <= level)tax = income * RATE1;elsetax = level * RATE1 + (income - level) * RATE2;printf("Your taxes is %g.\n", tax);printf("Please enter next type in integer:(q to quit)\n"); }printf("That's all!\n");return 0;}/* programming exercise 7-11 */ #include#include#define WT_LEVEL1 5#define WT_LEVEL2 20#define FR_LEVEL1 3.5#define FR_LEVEL2 10#define FR_LEVEL3 8#define FR_OVER 0.1#define DISCOUNT 0.05#define AC_PRC 1.25#define BT_PRC 0.65#define CR_PRC 0.89int main(void){char a, b, c;char ch;float a_wt = 0, b_wt = 0, c_wt = 0;float total_wt;float cost, total_cost, freight;int discount = 0;printf("************************************************\n");printf("Please choose the vegatable and weight you want:\n");printf("(type as follow, q to quit)\n");printf("a) artichoke; b) beet; c) carrot;\n");printf("************************************************\n");while ((ch = getchar()) != 'q'){switch (ch){case 'a':printf("You select artichoke, enter the weight:\n");scanf("%f", &a_wt);break;case 'b':printf("You select beet, enter the weight:\n");scanf("%f", &b_wt);break;case 'c':printf("You select carrot, enter the weight:\n");scanf("%f", &c_wt);。