#include<cstdio>
using namespace std;

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

int n, m, a[20][20], st[30], maxi;

void solve(){
    int sum=0, sol=0;
    for(int i=1; i<=n; ++i){
        sum=0;
        for(int j=1; j<=m; ++j)
            if(st[j]==1)
                sum-=a[i][j];
            else
                sum+=a[i][j];
        if(sum<-sum) sum=-sum;
        sol+=sum;
    }
    if(sol>maxi) maxi=sol;
}
void bkt(int k){
    if(k==m+1){
        solve();
        return;
    }
    st[k]=0;
    bkt(k+1);
    st[k]=1;
    bkt(k+1);
}
int main()
{
    fscanf(f, "%d%d", &n, &m);
    for(int i=1; i<=n; ++i)
        for(int j=1; j<=m; ++j)
            fscanf(f, "%d", &a[i][j]);
    maxi=-99999999;
    bkt(1);
    fprintf(g, "%d", maxi);
return 0;
}