#include <bits/stdc++.h>
using namespace std;

ifstream fin("flip.in");
ofstream fout("flip.out");

int n, m, x, lin[20], col[20], s = 0;

int main()
{


    fin >> n >> m;

    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            fin >> x;
            lin[j] += x;
            col[i] += x;
            s += x;
        }
    }

    for(int i = 1; i <= n; i++){
        if(col[i] < 0){
            s = s - col[i];
            s = s + (abs(col[i]));
        }
    }

    for(int i = 1; i <= m; i++){
        if(lin[i] < 0){
            s = s - lin[i];
            s = s + (abs(lin[i]));
        }
    }

    fout << s;

    return 0;
}