#include <iostream>
#include <fstream>
#include <bits/stdc++.h>
using namespace std;

ifstream in("flip.in");
ofstream out("flip.out");

const int nmax=40;
int a[nmax][nmax],sum[nmax],n,m,ans;


int main(){
in >>n>>m;
for(int i=1;i<=n;i++)
 for(int j=1;j<=m;j++){
 	in >>a[i][j];
 }
 ans=-2e18;
 for(int i=0;i<(1<<n);i++){
 	memset(sum,0,sizeof(sum));
 	
 	for(int k=1;k<=n;k++)
 	 for(int j=1;j<=m;j++){
 	 	sum[j]+=((i&(1<<k)) ? a[k][j] : -a[k][j]);
	  }
 	
 	int s=0;
 	for(int j=1;j<=m;j++)s+= abs(sum[j]);
 	
 	ans=max(ans,s);
 }
 out <<ans;
 return 0;
}