#include <iostream>
#include <cstdio>
using namespace std;
int cmax;
int n,i,j,m,v[17][17],s[17],ans;
void r(int k)
{
	if (k == n+1)
	{
		int tempans = 0;
		for (int i = 1; i <= m; ++i)
			tempans += s[i] > 0 ? s[i] : -s[i];
		ans = max(ans, tempans);
		return;
	}
	r(k+1);

	for (int i = 1; i <= m; ++i)
	{
		s[i]-=2*v[k][i];
	}

	r(k+1);

	for (int i = 1; i <= m; ++i)
	{
		s[i]+=2*v[k][i];
	}
}

int main()
{
    FILE *in,*out;
    in=fopen("flip.in","r");
    out=fopen("flip.out","w");
    fscanf(in,"%d %d",&n,&m);
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
        {
            fscanf(in,"%d ",&v[i][j]);
            s[j]+=v[i][j];
        }

    }
    r(1);
    fprintf(out,"%d",ans);
    return 0;
}