编辑代码

class Main {
	public static void main(String[] args) {
        int[] arr = {1,2,3};
        int result = fengjie(3,arr);
		System.out.println("结果为："+result);
        int result1 = fengjie1(arr);
		System.out.println("结果为："+result1);
	}


    //递归
    public static int fengjie(int length,int[] arr){
        if(length==1){
            return arr[0];
        }
        return arr[length-1]+fengjie(length-1,arr);
    }
    
    //递推
    public static int fengjie1(int[] arr){
        int num = 0;
        for(int i=0;i<arr.length;i++){
            num+=arr[i];
        }
        return num;
    }



}