一个球从100米高度自由落下，每次落地后反跳回原高度的一半；
再落下，求它在第10次落地时，共经过多少米？第10次反弹多高？
法1：用面向对象的方式模拟出球的运动过程来求解。
（第一版）
public class Boll {
double heigh = 100;
double len = 0;
public Boll(){
}
public void fall(){
len += heigh;
}
public void rebound(){
heigh /= 2;
len += heigh;
}
public static void main(String[] args) {
int n = 10;
Boll bo = new Boll();
for (int i = 0; i < n; i++) {
bo.fall();
bo.rebound();
}
System.out.println("第"+n+"落地的总路径长度是："+(bo.len-bo.heigh));
System.out.println("第"+n+"次反弹的高度是："+bo.heigh);
}
}（第二版）
public class Ball {
private double height;
private int downTimes;
private int jumpTimes;
private double sum;
public Ball(double height) {
this.height = height;
}
public void fall(){
downTimes++;
sum += height;
}
public void jump(){
jumpTimes++;
height /= 2;
sum += height;
}
public static void main(String[] args) {
Ball ball = new Ball(100);
while(true){
ball.fall();
if(ball.downTimes==10){
System.out.println("sum="+ball.sum);
break;
}
ball.jump();
}
System.out.println("------------");
Ball ball2 = new Ball(100);
while(true){
ball2.fall();
ball2.jump();
if(ball2.jumpTimes==10){
System.out.println("height="+ball2.height);
break;
}
}
}
}法2：用面向过程的方式以for循环的方式模拟出球的运行过程来求解
public class Boll {
double heigh = 100;
double len = 0;
public Boll(){
}
public void fall(){
len += heigh;
}
public void rebound(){
heigh /= 2;
len += heigh;
}
public static void main(String[] args) {
int n = 10;
Boll bo = new Boll();
for (int i = 0; i < n; i++) {
bo.fall();
bo.rebound();
}
System.out.println("第"+n+"落地的总路径长度是："+(bo.len-bo.heigh));
System.out.println("第"+n+"次反弹的高度是："+bo.heigh);
}
}
