Fibonacci 斐波那契数列 面向对象 java 版本 代码

import java.util.ArrayList;

public class Main {

public static void main(String[] args) {
ArrayList<Rabbit> Rabbitlist = new ArrayList<Rabbit>();
Rabbitlist.add(new Rabbit());
for (int i = 0; i < 20; i++) {
System.out.print(Rabbitlist.size());
System.out.print(",");
for (Rabbit rabbit : (ArrayList<Rabbit>) Rabbitlist.clone()) {
if (rabbit.isSmall()) {
rabbit.Growing();
} else {
Rabbitlist.add(rabbit.Create());
}
}
}
}
}

class Rabbit {

boolean small;

Rabbit() {
small = true;
}

public Rabbit Growing() {
small = false;
return null;
}

public Rabbit Create() {
return new Rabbit();
}

public boolean isSmall() {
return small;
}
}