#include<cstdio>


int lin, col, sumaMax;
int stivaLin[17];
int a[17][17];


void ActualizareMax()
{

int i, j, s, sum;



sum = 0;

for(j = 1; j <= col; j++)

{

s = 0;

for(i = 1; i <= lin; i++) s += stivaLin[i] * a[i][j];

s = s < 0 ? -s : s;

sum += s;

}

if(sumaMax < sum) sumaMax = sum;
}


void Back(int top)
{

if(top == lin + 1)

{

ActualizareMax();

return ;

}

stivaLin[top] = -1;

Back(top + 1);

stivaLin[top] = 1;

Back(top + 1);
}


int main()
{

int i, j;



freopen("flip.in", "r", stdin);

freopen("flip.out", "w", stdout);


scanf("%d%d", &lin, &col);

for(i = 1; i <= lin; i++)

for(j = 1; j <= col; j++)

scanf("%d", &a[i][j]);


Back(1);



fclose(stdin);

printf("%d\n", sumaMax);

fclose(stdout);



return 0;