c++作业

第一章1-1/*求一个整数的10倍*/#include<iostream.h>void main(){ int a,b;cout<<"请输入一个任意整数："<<'\n';cin>>a;b=10*a;cout<<"这个数的10倍是："<<b<<endl;}1-2/*求两个数中较小的一个*/#include<iostream.h>void main(){float a,b;cout<<"请输入两个数：";cin>>a>>b;cout<<"这两个数中较小的数为："<<(a>b?b:a)<<endl;}1-3/*求圆的周长和半径*/#include<iostream.h>void main(){float radius,x(3.141592653),c,s;cout<<"请输入圆的半径："<<endl;cin>>radius;c=2*x*radius;s=x*radius*radius;cout<<"圆的周长为："<<c<<'\n'<<"圆的面积为："<<s<<'\n'; }1-4/*将10000秒化为小时分秒*/#include<iostream.h>void main(){int a,b,c;a=10000/360;b=10000%360/60;c=10000%360%60;cout<<"10000秒是"<<a<<"小时"<<b<<"分"<<c<<"秒";}1-5/*将三位正整数各位分三行输出*/#include<iostream.h>void main(){int a,b,c,d;cout<<"请输入一个三位数：";cin>>a;b=a/100;c=a%100/10;d=a%10;cout<<d<<'\n'<<c<<'\n'<<b<<'\n';}第二章2-1#include<iostream.h>void main(){int n,y;cout<<"请输入一个整数："<<endl;cin>>n;if(n>0) y=n+1;else if(n==0) y=0;else y=n*n;cout<<"y="<<y<<endl;}2-2#include<iostream.h>void main(){char word;cout<<"请输入一个任意字符：\n";cin>>word;if(word>='0'&&word<='9')cout<<"输入的字符是数字\n";else if(word>='a'&&word<='z')cout<<"输入的字符是小写字母\n";else if(word>='A'&&word<='Z')cout<<"输入的是大写字母\n";else cout<<"输入的是其他字符\n";}2-3#include<iostream.h>void main(){double a(0),b(-1),n(0);for(;1/(2*n+1)>=1.0e-6;){b*=-1;a+=b/(2*n+1);n++;}cout<<"π="<<4*a<<endl;}2-7#include<iostream.h>void main(){float F(-30),C;for(;F<=100;F=F+5){C=(F-32)*5/9;cout<<"华氏"<<F<<"度=摄氏"<<C<<"度"<<endl;}}2-4#include<iostream.h>void main(){int i=5,j,a,b(0);for(;i<=7;i++){a=1;{for(j=1;j<=i;j++)a*=j;}b+=a;}cout<<"5!+6!+7!="<<b<<endl;}2-5#include<iostream.h>void main(){int i,j,count(0);cout<<"从2开始100个素数：";for(i=2;count<=100;i++){for(j=2;j<=i;j++){if(i%j!=0) continue;else if (i==j) {cout<<i<<" ";count++;}else break;}}}2-6/*百钱百鸡问题*/#include<iostream.h>void main(){int i,j,k;for(i=0;i<=19;i++){for(j=0;j<=100-i;j++){k=100-i-j;if(15*i+9*j+k==300){cout<<"公鸡"<<i<<"只\n";cout<<"母鸡"<<j<<"只\n";cout<<"小鸡"<<k<<"只\n";break;}}}}第三章3-1#include<iostream.h>void main(){float score[10],ave,sum(0),a(0),b(0);cout<<"请输入10个同学的成绩：";for(int i=0;i<=9;i++){cin>>score[i];sum+=score[i];}ave=sum/10;for(int j=0;j<=9;j++){if(score[j]>ave) a++;if(score[j]<60) b++;}cout<<"平均分"<<ave<<endl;cout<<"大于平均分的人数"<<a<<endl;cout<<"小于60分的人数"<<b<<endl;}3-2#include<iostream.h>void main(){char str[80];int a(0),i(0),j(0);cout<<"请输入一串字符："<<endl;cin>>str;while(str[j]!='\0'){if(str[j]=='a') a++;if(str[j]=='i') i++;j++;}cout<<"a出现的次数："<<a<<endl;cout<<"i出现的次数："<<i<<endl;cout<<"这串字符为："<<str<<endl;}3-3#include<iostream.h>void main(){float a[3][3],sum1(0),sum2(0);cout<<"输入一个3×3的二维数组："<<endl;for(int i=0;i<3;i++)for(int j=0;j<3;j++)cin>>a[i][j];for(int m=0,n=2;m<3;m++,n--){sum1+=a[m][m];sum2+=a[m][n];}cout<<"主对角线之和："<<sum1<<endl;cout<<"次对角线之和："<<sum2<<endl;}3-4#include<iostream.h>void main(){int a[11]={2,4,5,8,12,14,16,18,20,30},x,i,j,k;cout<<"请输入一个任意整数："<<endl;cin>>x;for(i=0;i<=10;i++){if(x<a[i]){for(j=10;j>i;j--) a[j]=a[j-1];a[i]=x;break;}}for(k=0;k<=10;k++)cout<<a[k]<<" ";}3-5#include<iostream.h>void main(){int a[5][3],i,j,b[5]={0},x;cout<<"请输入一个5行3列的数组："<<endl;for(i=0;i<5;i++)for(j=0;j<3;j++)cin>>a[i][j];for(i=0;i<5;i++)for(j=0;j<3;j++)b[i]+=a[i][j];for(i=0;i<5;i++)for(j=0;j<5-i;j++)if(b[j]>b[j+1]){x=b[j+1];b[j+1]=b[j];b[j]=x;}for(i=0;i<5;i++)cout<<b[i]<<" ";}第四章#include<iostream.h>#include<string.h>#define N 80float count(char a[]);void main(){char a[N];float b;cout<<"请输入一串字符："<<endl;cin.getline(a,N);b=strlen(a);cout<<"数字所占百分比为："<<count(a)/b<<endl;}float count(char a[]){int i(0);float count(0);while(a[i]!='\0'){if(a[i]>='\0'&&a[i]<='\9')count++;i++;}return count;}4-2#include<iostream.h>int fmax(int x,int y);int fmin(int x,int y);void main(){int a,b;cout<<"请输入两个整数："<<endl;cin>>a>>b;cout<<"这两个数的最大公约数："<<fmax(a,b)<<endl;cout<<"这两个数的最小公倍数："<<fmin(a,b)<<endl; }int fmax(int x,int y){int i=(x>=y?y:x);for(;i>=1;i--)if(x%i==0&&y%i==0){return i;break;}int fmin(int x,int y){int i=(x>=y?x:y);for(;i<=x*y;i++)if(i%x==0&&i%y==0){return i;break;}}4-3#include<iostream.h>int f(int x);float f(float x);double f(double x);void main(){int a;float b;double c;cout<<"请分别输入一个整数、一个单浮点数、一个双浮点数："<<endl;cin>>a>>b>>c;cout<<"整数的绝对值："<<f(a)<<endl;cout<<"单浮点数的绝对值："<<f(b)<<endl;cout<<"双浮点数的绝对值："<<f(c)<<endl;}int f(int x){if(x>=0) return x;else return -x;}float f(float x){if(x>=0) return x;else return -x;}double f(double x){if(x>=0) return x;else return -x;}4-4/*从一串字符中去除与另一串字符共同含有的字符*/#include<iostream.h>#include<string.h>#define N 80void delchar(char *s1,char s2);void main(){char s1[N],s2[N],*p;cout<<"输入第一串字符："<<endl;cin.getline(s1,N);cout<<"输入第二串字符："<<endl;cin.getline(s2,N);p=s1;for(int i=0;s2[i]!='\0';i++)delchar(p,s2[i]);cout<<"从第一串字符中去除与第二串字符相同的字符后得："<<s1<<endl; }void delchar(char *s1,char s2){for(;*s1!='\0';s1++)if(*s1==s2)for(;*s1!='\0';s1++)*s1=*(s1+1);}4-5#include<iostream.h>int function(int n,int k);void main(){int n,k;cout<<"输入一个整数："<<endl;cin>>n;cout<<"输入k的值："<<endl;cin>>k;cout<<n<<"从右数第"<<k<<"个数字是"<<function(n,k)<<endl;}int function(int n,int k){int i,j,m;m=n;for(i=0;m!=0;i++)m/=10;if(k<1||k>i) return 0;else{for(j=1;j<k;j++){n/=10;}n=n%10;return n;}}4-6#include<iostream.h>#define N 80void avel(int p[N][N],int m,int n);void main(){int m,n,p[N][N],i,j;cout<<"输入数组的行数与列数："<<endl;cout<<"行：";cin>>m;cout<<"列：";cin>>n;cout<<"输入"<<m<<"行"<<n<<"列的二维数组："<<endl;for(i=0;i<m;i++)for(j=0;j<n;j++)cin>>p[i][j];avel(p,m,n);}void avel(int p[N][N],int m,int n){int i,j,sum;for(i=0;i<m;i++){sum=0;for(j=0;j<n;j++)sum+=*(*(p+i)+j);cout<<"第"<<i<<"行的平均值是："<<sum/n<<endl;}}4-7#include<iostream.h>#include<string.h>#define N 80char ch;int find(char a[]);void main(){char a[N];cout<<"输入字符串："<<endl;cin.getline(a,N);cout<<"输入要寻找的字符："<<endl;cin>>ch;find(a);}int find(char a[]){int i,j(0);for(i=0;a[i]!='\0';i++){if(a[i]==ch){cout<<ch<<"第一次出现的位置为"<<(i+1)<<endl;j++;}}if(j==0) {cout<<"无"<<ch<<"字符"<<endl;}return 0;}4-8#include<iostream.h>int chan(int x,int y);void main(){int n,m;cout<<"输入需要转换的十进制整数："<<endl;cin>>n;cout<<"输入要转化成的进制数："<<endl;cin>>m;chan(n,m);}int chan(int x,int y){int *p,i(0),a[80];p=a;if(x<y)cout<<"转化为"<<y<<"进制后为："<<x<<endl;if(x>=y){{for(;x>=y;){*p=x%y;x=x/y;p++;i++;}*p=x;}cout<<"转化为"<<y<<"进制后为：";for(;i>=0;i--){cout<<*p;p--;}cout<<endl;}return 0;}第五章5-1#include<iostream.h>class Date{int year,month,day;public:Date();int NumberOfDays();int y(){return year;}int m(){return month;}int d(){return day;}};Date::Date(){cout<<"请分别输入年月日";cin>>year>>month>>day; }int Date::NumberOfDays(){int sum(0),r;int d[13];if (year%100==0) {if (year%400==0) r=1;else r=0;}else {if (year%4==0) r=1;else r=0;}d[1]=d[3]=d[5]=d[7]=d[8]=d[10]=d[12]=31;d[4]=d[6]=d[9]=d[11]=30;if (r==1) d[2]=29;if (r==0) d[2]=28;for(int i=1;i<month;i++) sum+=d[i];sum+=day;return sum;}void main(){Date a;cout<<a.y()<<"年"<<a.m()<<"月"<<a.d()<<"日是"<<a.y()<<"年的第"<<a.NumberOfDays()<<"天"<<endl;}5-2#include<iostream.h>class Integer{int d;public:void setD(int);int getD(){return d;}void IsOdd();void IsPrime();};void Integer::setD(int m){d=m;}void Integer::IsOdd(){if (d%2==0) cout<<"是偶数"<<endl;else cout<<"不是偶数"<<endl;}void Integer::IsPrime(){int i;for (i=2;i<d;i++)if (d%i==0) break;if (i==d) cout<<"是素数"<<endl;else cout<<"不是素数"<<endl;}void main(){Integer d1,d2;d1.setD(15);d2.setD(31);cout<<15;d1.IsOdd();cout<<15;d1.IsPrime();cout<<31;d2.IsOdd();cout<<31;d2.IsPrime();}5-3#include<iostream.h>class line{double A,B,C;public:line();friend int par(line,line);friend void p(line,line);};line::line(){cout<<"请输入标准方程Ax+By+C=0参数A,B,C"<<endl;cin>>A>>B>>C;}int par(line a,line b){double m,n,p;m=a.A/b.A;n=a.B/b.B;p=a.C/b.C;if (m==n&&n==p) {cout<<"两直线平行"<<endl;return 1;}else {cout<<"两直线相交"<<endl;return 0;}}void p(line a,line b){double x,y;x=(b.C*a.B+a.C*b.B)/(a.A*b.B-b.A*a.B);y=-(b.A*a.C+a.A*b.C)/(a.A*b.B-b.A*a.B);cout<<"交点为("<<x<<","<<y<<")"<<endl; }void main(){line a,b;if (par(a,b)==0) p(a,b);}第八章8-1#include<fstream.h>#include<stdlib.h>void main(){ofstream fout("e:\\file1.txt");if(!fout){cout<<"Cannot open the file!"<<endl;exit(1);}char *str;str=new char[80];cout<<"请输入字符串: "<<endl;cin.get(str,80,'#');fout<<str;fout.close();delete []str;}8-2#include<fstream.h>#include<stdlib.h>void main(){ifstream fin("e:\\file1.txt");if(!fin){cout<<"Cannot open the file!"<<endl;exit(1);}char *str;str=new char[80];fin>>str;cout<<str<<endl;fin.close();delete str;}8-3#include<fstream.h>#include<stdlib.h>int count1(0),count2(0);void main(){char *str,*s1,*s2;int i;str=new char[80];s1=new char[80];s2=new char[80];cout<<"请输入字符串："<<endl;cin.getline(str,80);for (i=0;i<=80;i++){if (str[i]=='\0') break;else {if (str[i]>='0'&&str[i]<='9') {s1[count1]=str[i];count1++;}else {s2[count2]=str[i];count2++;}}}s1[count1]='\0';s2[count2]='\0';ofstream fout1("e:\\shuzi.txt");if(!fout1){cout<<"Cannot open the file!"<<endl;exit(1);}fout1<<s1;fout1.close();ofstream fout2("e:\\zimu.txt");if(!fout2){cout<<"Cannot open the file!"<<endl;exit(1);}fout2<<s2;fout2.close();delete str,s1,s2;}。