题解 | A394.计算矩阵边缘元素之和

#include <bits/stdc++.h>
using namespace std;
int main(){
    int a[105][105] , n , m , sum = 0;
    cin >> n >> m;
    for(int i = 1;i <= n;i++){
        for(int j = 1;j <= m;j++){
            cin >> a[i][j];
            if(i == 1 || i == n || j == 1 || j == m){
                sum += a[i][j];
            }
        }
    }
    cout << sum;
    return 0;
}