#include <stdio.h>
#include <stdlib.h>
#define MAXN 16

int v[MAXN][MAXN], n, m;
int main(){
    FILE*fi,*fo;
    fi=fopen("flip.in","r");
    fo=fopen("flip.out","w");
    fscanf(fi,"%d%d", &n, &m);
    for(int i=0;i<n;i++)
        for(int j=0;j<m;j++)
            fscanf(fi,"%d", &v[i][j]);
    long long config=0, max=-1000000000000000;
    for(config=0;config<(1<<m);config++){
        long long sum=0LL;
        for(int i=0;i<n;i++){
            long long sum2=0LL;
            for(int j=0;j<m;j++){
                if(config&(1<<j))
                    sum2-=v[i][j];
                else
                    sum2+=v[i][j];
            }
            if(sum2>0)
                sum+=sum2;
            else
                sum-=sum2;
        }
        if(sum>max)
            max=sum;
    }
    fprintf(fo,"%lld", max);
    fclose(fi);
    fclose(fo);
    return 0;
}