#include<stdio.h>

long i, j, p=1, sum, s, smax=0, t[20][20], x[20];
int k, l, n, m, y[20];


int main(){

    freopen("flip.in", "r", stdin);
    freopen("flip.out", "w", stdout);

    scanf("%d%d", &n, &m);
    for (i=1; i<=n; i++)
        for (j=1; j<=m; j++)
            scanf("%ld", &t[i][j]);

    p=(p<<n)-1;
    for (i=1; i<=p; i++){
        for (j=1; j<=n; j++)
            y[j]=i>>(j-1)& 1;


    for (k=1; k<=m; k++){
        sum=0;
        for (l=1; l<=n; l++)
            if (y[l]==1) sum-=t[l][k];
            else sum+=t[l][k];
        if (sum<0) x[k]=-sum;
        else x[k]=sum;
    }
    s=0;
    for (k=1; k<=m; k++)
        s=s+x[k];
        if (s>smax) smax=s;
    }
 printf("%ld", smax);
 return 0;
}