#include<bits/stdc++.h>
using namespace std;
ifstream fin("flip.in");
ofstream fout("flip.out");

int sol[20],lgsol,mat[20][20];

int n,m,ans;

int Scor(){

int i,j,sum=0,s;

for(j=1;j<=m;j++){
    s=0;
    for(i=1;i<=n;i++){
        if(sol[i-1])
            s=s-mat[i][j];
        else
            s=s+mat[i][j];
    }
    sum+=abs(s);
}

return sum;

}

void solve(){

int i,j,k;

for(k=0;k<(1<<n);k++){

    for(i=0;i<=n;i++)
      sol[i]=0;

    for(i=0;i<n;i++)
        if(k & (1<<i))
           sol[i]=1;

    ans=max(ans,Scor());
}

}

int main(){

int i,j;

fin>>n>>m;

for(i=1;i<=n;i++)
    for(j=1;j<=m;j++)
        fin>>mat[i][j];

solve();

fout<<ans;

}