递归解决累加和兔子繁殖

package digui;

public class DiGui {
    public static void main(String[] args) {
        System.out.println(sum(100));
        
for(int i=1;i<15;i++){
    System.out.println(i+":"+rabbit(i));
}
            
        
    }
//1+2+100
public static int sum(int a){
        if(a==1){
            return 1;
        }else{
            return a+sum(a-1);
        }
    }
//兔子繁殖
public static int rabbit(int b){
    if(b==1 || b==2){
        return 1;
    }else{
        return rabbit(b-1)+rabbit(b-2);
    }
}
}