#include <stdio.h>
#include <stdlib.h>

int v[17][17],S,sol[17],n,m,sl;

void check()
{
    int s=0,sc=0,i,j;

    for(i=0;i<m;i++)
    {
        sc=0;
        for(j=0;j<n;j++)
        {
            sc+=v[j][i]*sol[j];
        }
        if(sc<0) s+=-sc;
        else s+=sc;
    }

    if(s>S) S=s;
}

void back(int k)
{
    if(k==n) check();
    else
    {
            sol[k]=1; back(k+1);
            sol[k]=-1; back(k+1);
    }
}

int main()
{
    FILE *f=fopen("flip.in","r");
    FILE *fp=fopen("flip.out","w");
    int i,j;

    fscanf(f,"%d %d",&n,&m);

    for(i=0;i<n;i++)
        for(j=0;j<m;j++)
        {
            fscanf(f,"%d",&v[i][j]);
        }

    back(0);
    fprintf(fp,"%d",S);


    return 0;
}