#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(a) (a).begin(), (a).end()
#define forn(i,a,b) for (int i = a; i <= b; i++)
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define rc(s) return cout<<s,0
#define rcc(s) cout<<s,exit(0)
#define er erase
#define in insert
#define pi pair <int, int>
# define sz(x) (int)((x).size())
#define int long long

const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};

const ll inf = 0x3f3f3f3f3f3f3f;
const ll mod = 1999999973;
const int N = 16;

int a[N][N],n,m,sum[N];


int32_t main(){
ios_base::sync_with_stdio(0); cin.tie(0); cerr.tie(0); cout.tie(0);

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

    cin >> n >> m;

    forn(i,1,n){
        forn(j,1,m){
            cin>>a[i][j];
        }
    }

    int ans = -2e18;

    forn(i,0,(1<<n)){

        memset(sum, 0, sizeof(sum));

        forn(k,1,n){
            forn(j,1,m){
                sum[j] += ((i&(1<<k)) ? -a[k][j] : a[k][j]);
            }
        }

        int s = 0;
        forn(j,1,m)s += abs(sum[j]);

        ans = max(ans , s);

    }

    cout << ans << '\n';


return 0;
}