#include<stdio.h>
using namespace std;

FILE*f=fopen("flip.in","r");
FILE*g=fopen("flip.out","w");

int n,m,i,j,s,smax,t,k,a[20][20];

int main() {

    fscanf(f,"%d%d",&n,&m);
    for(i=1;i<=n;i++) {
        for(j=1;j<=m;j++) fscanf(f,"%d",&a[i][j]);
    }

    for(i=1;i<=(1<<m);i++) {
        s=0;
        for(k=1;k<=n;k++) {
            t=0;
            for(j=1;j<=m;j++) {
               if(i&(1<<j)) t=t+a[k][j];
               else t=t-a[k][j];
            }
            if(t>-t) s=s+t;
            else s=s-t;
        }
        if(s>smax) smax=s;
    }

    fprintf(g,"%d",smax);

    return 0;
}