func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     ;     int n, m;     cin >> n >> m;     int a[n][m];     for (int i = 0; i < n; i++)       for (int j = 0; j < m; j++) cin >> a[i][j];     int flag = 0;     for (int i = n - 2; i >= 1; i--) {       for (int j = m - 2; j >= 1; j--) {         if ((a[i + 1][j] == a[i][j - 1]) || (a[i][j + 1] == a[i - 1][j])) {           flag = 1;           break;         } else if (a[i][j] == 0) {           a[i][j] = min(a[i + 1][j], a[i][j + 1]) - 1;         }         if (a[i][j] <= a[i - 1][j] || a[i][j] <= a[i][j - 1]) {           flag = 1;           break;         }       }     }     int sum = 0;     for (int i = 0; i < n - 1; i++) {       if (a[i][0] >= a[i + 1][0] || a[i][m - 1] >= a[i + 1][m - 1]) {         flag = 1;         break;       }     }     for (int i = 0; i < m - 1; i++) {       if (a[0][i] >= a[0][i + 1] || a[n - 1][i] >= a[n - 1][i + 1]) {         flag = 1;         break;       }     }     if (flag == 1) {       cout << -1 <<   n ;       return 0;     }     for (int i = 0; i < n; i++) {       for (int j = 0; j < m; j++) sum += a[i][j];     }     cout << sum;     return 0;   }   