#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>

typedef long long ll;

const ll mod=1e9+7;

#define all(x) x.begin(),x.end()
#define allr(x) x.rbegin(),x.rend()
#define rc(x)  return cout<<x<<"\n",0
#define sz(s)  (int) s.size()
#define pb push_back
#define mp make_pair
#define fr first
#define sc second

using namespace std;

ll a[20][20],suma[20],sum,ans=-2e16;

int main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	ifstream cin("flip.in");
	ofstream cout("flip.out");
	int n,m;
	cin >> n >> m;
	for (int i=1; i<=n; i++) {
		for (int j=1; j<=m; j++) {
			cin >> a[i][j];
		}
	}
	
	for (int i=1; i<=1<<n; i++) {
		memset(suma, 0, sizeof(suma));
		for (int j=1; j<=n; j++) {
			for (int g=1; g<=m; g++) {
				if (i&(1<<j)) {
					suma[g]+=-a[j][g];
				}
				else {
					suma[g]+=a[j][g];
				}
			}
		}
		sum=0;
		for (int q=1; q<=m; q++) {
			sum+=abs(suma[q]);
		}
		ans=max(sum,ans);
	}
	cout << ans;

}