斯坦福大学公开课：编程方法学ASSIGNMENT1

斯坦福大学公开课：编程方法学

ASSIGNMENT1

这个是根据

Assignment #1: Email and Karel the Robot

Karel problems due: 1:15pm on Friday, April 12th ,2013

自己写的代码，没有做过优化，这次的作业中Problem3的代码有问题，只能实现在大多数的世界中使用，在1 X N这种会失效还没有修改，刚接触这门课程，还是挺有趣的，卡雷尔机器人程序。

我先声明了一个通用的类, 然后再做的作业.

import stanford.karel.*;

public class 通用 extends SuperKarel{

public void moveBackToWall(){

turnAround();

while(frontIsClear()){

move();

}

}

public void moveToWall(){

while(frontIsClear()){

move();

}

}

public void moveBackward(){

turnAround();

move();

turnAround();

}

public void turnBack(){

turnLeft();

turnLeft();

}

}

problem1

/*

* File: CollectNewspaperKarel.java

* --------------------------------

* At present, the CollectNewspaperKarel subclass does nothing.

* Your job in the assignment is to add the necessary code to

* instruct Karel to walk to the door of its house, pick up the

* newspaper (represented by a beeper, of course), and then return

* to its initial position in the upper left corner of the house.

*/

public class CollectNewspaperKarel extends 通用 {

public void run(){

moveToWall();

turnRight();

move();

turnLeft();

move();

pickBeeper();

turnBack();

move();

turnRight();

moveToWall();

turnLeft();

moveToWall();

putBeeper();

turnBack();

}

} problem2

public class UnitedNationsKarel extends 通用 {

public void run(){

while(frontIsClear()){

if(beepersPresent()){

pickBeeper();

buildHouse();

}

if(frontIsClear()){

move();

}

}

}

private void buildHouse(){

getReady();

build();

finish();

}

private void getReady(){

moveBackward();

turnLeft();

}

private void finish(){

turnLeft();

}

private void build(){

buildPart();

nextToWork();

buildPart();

getNext();

buildPart();

}

private void buildPart(){

putBeeper();

move();

putBeeper();

move(); putBeeper();

}

private void nextToWork(){

move();

turnRight();

move();

turnRight();

}

private void getNext(){

turnAround();

nextToWork();

}

}

problem3

/*

* File: CheckerboardKarel.java

* ----------------------------

* When you finish writing it, the CheckerboardKarel class should draw

* a checkerboard using beepers, as described in Assignment 1. You

* should make sure that your program works for all of the sample

* worlds supplied in the starter folder.

*/

public class CheckerboardKarel extends 通用 {

public void run(){

while(leftIsClear()){

while(frontIsClear()){

putRow();

}

moveToNextStreet();

}

while(frontIsClear()){

putRow();

}

checkBeeper();

}

private void putRow(){

putBeeper();

if(frontIsClear()){ move();

}

if(frontIsClear()){

move();

}

}

private void moveToNextStreet(){

checkBeeper();

moveBackToWall();

moveForPutRow();

}

private void checkBeeper(){

moveBackward();

if(beepersPresent()){

}else{

move();

putBeeper();

}

}

private void moveForPutRow(){

turnRight();

if(beepersPresent()){

move();

turnRight();

move();

}else{

move();

turnRight();

}

}

}

problem4

/*

* File: MidpointFindingKarel.java

* -------------------------------

* When you finish writing it, the MidpointFindingKarel class should

* leave a beeper on the corner closest to the center of 1st Street

* (or either of the two central corners if 1st Street has an even * number of corners). Karel can put down additional beepers as it

* looks for the midpoint, but must pick them up again before it

* stops. The world may be of any size, but you are allowed to

* assume that it is at least as tall as it is wide.

*/

public class MidpointFindingKarel extends 通用 {

public void run(){

fullOfBeepers();

while(beepersPresent()){

changeForTake();

takeOneBeeper();

}

turnAround();

move();

}

private void fullOfBeepers(){

putBeeper();

while(frontIsClear()){

move();

putBeeper();

}

}

private void changeForTake(){

moveToWall();

turnAround();

}

private void takeOneBeeper(){

for(int i=0;i<15;i++){

if(beepersPresent()){

}else{

move();

}

}

move();

checkBeeper();

}

private void checkBeeper(){

if(beepersPresent()){

moveBackward();

pickBeeper();