用c++把 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 计算这组数右上角到左下角对角线的和

1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25计算这组数右上角到左下角五个数字的和

参考如下，欢迎采纳哈

#include <iostream>
using namespace std;

int main() {
    int arr[][5] =  {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25};

    int i, sum = 0;
    for (i = 0; i < 5; i++)
    {
        sum += arr[i][5 - i - 1];
    }

    cout <<"右上角到左下角对角线的和 : "<< sum;

    return 0;
}