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

int a[20][20];

int main() {
    ifstream cin( "flip.in" );
    ofstream cout( "flip.out" );
    int n, m, l, c, i, j;
    long long suma, s, maxx;
    cin >> n >> m;
    for( l = 0; l < n; l++ )
        for( c = 0; c < m; c++ ){
            cin >> a[l][c];
        }
    maxx = -1;
    for( i = 0; i < ( 1 << n ); i++ ){
        suma = 0;
        for( c = 0; c < m; c++) {
            s = 0;
            for( l = 0; l < n; l++ ){
                if( i & (1<<l) )
                    s -= a[l][c];
                else
                    s += a[l][c];
            }
            if( s < 0 ) 
              s = -s;
            suma += s;
        }
        if( suma > maxx ) 
          maxx = suma;
    }
    cout << maxx;
}