#include <iostream>
#include <stdio.h>
#include <math.h>
using namespace std ;
  
int a[17][17],col[17],v[17];
int n, m,maxim = 0;
  
void citire(){
    freopen("flip.in","r",stdin);
    cin >> n >> m ;
    for (int i = 0 ; i < n ; i++)
        for (int j = 0 ; j < m ; j++){			
            cin >> a[i][j] ;
			col[j] += a[i][j];
		}
}

void summa(int k){
	int sum = 0 ;
	for (int i = 0 ; i < m ; i++){
		int s = 0 ;
		for (int j = 1 ; j < k ; j++)
			s+= a[v[j]][i];
		sum += abs(s[i]  - 2*s);
	}
	maxim = max(maxim,sum);
}
  
int main(){
    
    citire();
	summa(0);
	
	int k = 1;
	v[1] = -1;
	while (k > 0) {
		if (v[k] < n-1) {
			v[k]++;
			summa(k);
			k++;
			v[k] = v[k-1];
		}
		else k--;
	}
	
	freopen("flip.out","w",stdout);
    cout << maxim ;
    return 0  ;
}