#include <cstdio>

using namespace std;

long a[17][17],n,m,i,j,x[17],max1;

void suma()
{long s=0,i,j,sp;
for(int j=1;j<=m;j++)
{sp=0;
for(int i=1;i<=n;i++)
{sp+=a[i][j]*x[i];
}
if(sp<0) sp=sp*(-1);
s+=sp;
}
if(s>max1) max1=s;
}


void back(int k)
{int i;
if (k<n)
for (i=1;i<=2;i++)
{x[k]*=-1;
suma();
back(k+1);
}
}

int main()
{FILE *f1 = fopen("flip.in","r");
FILE *f2 = fopen("flip.out","w");
fscanf(f1,"%ld%ld",&n,&m);
for (i=1;i<=n;i++)
for (j=1;j<=m;j++) fscanf(f1,"%ld",&a[i][j]);
for (i=1;i<=16;i++) x[i]=1;
back(1);
fprintf(f2,"%ld\n",max1);
    return 0;
}