#include <cstdio>
#define max(a,b) (a > b ? a : b)
using namespace std;

const int nmx = 20;
const int inf = 0x3f3f3f3f;

int n,m,mat[nmx][nmx],c[nmx],r = -inf;

void input(){
    scanf("%d %d", &n, &m);
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= m; ++j)
            scanf("%d", &mat[i][j]);
}

void calc(){
    int total = 0;
    for(int i = 1; i <= n; ++i){
        int sum = 0;
        for(int j = 1; j <= m; ++j)
            sum += mat[i][j] * c[j];
        total += max(sum,-sum);
    }
    r = max(r,total);
}

void backtracking(int pos){
    if(pos == m + 1){
        calc();
        return;
    }
    c[pos] = 1;
    backtracking(pos+1);
    c[pos] = -1;
    backtracking(pos+1);
    return;
}

int main(){
    freopen("flip.in", "r", stdin);
    freopen("flip.out", "w", stdout);
    input();
    backtracking(0);
    printf("%d\n", r);
    return 0;
}