#include <bits/stdc++.h>
#define int int64_t

using namespace std;

int32_t main()
{
    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 sum = 0;
    bool have_ans = 1;
    for (int i = n - 2; i > 0; i--)
    {
        for (int j = m - 2; j > 0; j--)
        {
            if (!a [i] [j])
                a [i] [j] = min(a [i + 1] [j] - 1, a [i] [j + 1] - 1);
        }
    }
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            sum += a [i] [j];
            if ((i > 0 && a [i] [j] <= a [i - 1] [j]) || (a [i] [j] <= a [i] [j - 1] && j > 0))
                have_ans = 0;
        }
    }
    if (!have_ans)
        cout << "-1\n";
    else
        cout << sum << "\n";
}