#include <cstdio> 
 #define _CRT_SECURE_NO_WARNINGS   
  
  
int main()   
{   
    int a, b, o[20][20];   
  
    freopen("flip.in", "rt", stdin);   
    freopen("flip.out", "wt", stdout);   
  
    scanf ("%d%d", &a, &b);   
  
    for (int i = 0; i < a; i++)   
        for (int j = 0; j < b; j++)   
            scanf ("%d", o[i] + j);   
  
    int sol = 0;   
    for (int x = 0; x < 1 << b; x++)   
    {   
        int suma = 0;   
        for (int i = 0; i < a; i++)   
        {   
            int linie = 0;   
            for (int j = 0; j < b; j++)   
                if (x & (1 << j))   
                    linie += o[i][j];   
                else   
                    linie -= o[i][j];   
  
            if (linie > 0)   
                suma += linie;   
            else   
                suma -= linie;   
        }   
  
        if (sol < suma)   
            sol = suma;   
    }   
  
    printf ("%d\n", sol);   
    return 0;   
}