#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll const mod=1000000007;
ll const md=998244353;
ll mypowr(ll a,ll b) {ll res=1;if(b<0)b=0;a%=mod; assert(b>=0);
for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll mypow(ll a,ll b) {ll res=1;if(b<0)b=0;assert(b>=0);
for(;b;b>>=1){if(b&1)res=res*a;a=a*a;}return res;}
ifstream in("flip.in");
ofstream out("flip.out");
#define mp make_pair
#define pb push_back
#define pf push_front
#define fi first
#define se second

#define cin in
#define cout out

int a[20][20],b[20][20];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    cout<<fixed<<setprecision(15);

    ll n,m;
    cin>>n>>m;
    ll u=(1<<n);
    for(int i=1;i<=n;++i){
        for(int j=1;j<=m;++j){
            cin>>a[i][j];
        }
    }
    ll cnt=0;
    for(int i=0;i<u;++i){
        ll x=i,sum=1;
        for(int j=1;j<=n;++j){
            for(int t=1;t<=m;++t){
                b[j][t]=a[j][t];
            }
        }
        while(x){
            if(x&1){
                for(int j=1;j<=m;++j){
                    b[sum][j]-=2*b[sum][j];
                }
            }
            ++sum;
            x/=2;
        }
        sum=0;
        for(int j=1;j<=m;++j){
            ll p=0;
            for(int t=1;t<=n;++t){
                p+=b[t][j];
            }
           sum+=max(p,-p);
        }
        cnt=max(cnt,sum);
    }
    cout<<cnt<<'\n';


    return 0;
}