递归，斐波那契，对象类型数组

/*
递归：
方法自己调用自己

递归有两个条件：
1.有出口
2.不断向出口靠近

需求：1-100的和
*/
public class DiGui {
    public static void main(String[] args) {
        int result=getSum(100);
        System.out.println("result = " + result);
    }
    
    public static int getSum(int num){
        if(num==1){
            return 1;
        }
        return num=num+getSum(num-1);
    }
}

　　斐波那契

public class FeiBo {
    public static void main(String[] args) {
        int result=feibo(5);
        System.out.println("result = " + result);
    }


    public static int feibo(int n){
        if (n==1 ||n==2){
            return 1;
        }
        return feibo(n-1)+feibo(n-2);
    }
}

 对象类型数组

public class ArrObject {
    public static void main(String[] args) {
        Person p1=new Person();
        p1.name="lin1";
        p1.age=23;
        Person p2=new Person();
        p2.name="lin2";
        p2.age=22;
        Person arr1[]=new Person[]{p1,p2};
//        for (int i = 0; i < arr1.length; i++) {
//            arr1[i].show();
//        }
        for (Person p:arr1){
            p.show();
        }
    }
}

class Person{
    String name;
    int age;

    public void show(){
        System.out.println("name :"+name+" age :"+age);
    }
}