#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int n,s[20],i,j,m,a[20][20];
long long max;
FILE *f,*g;
void prelsuma()
{
int i,j;
long long s1,s2;
s1=0;
for(j=1;j<=m;j++) 
{s2=0; 
    for(i=1;i<=n;i++) 
        s2=s2+s[i]*a[i][j]; 
s1+=abs(s2); 
} 
if (s1>max) max=s1;
//printf("s1=%d",s1);
}
void back(int k)
{
if (k==n+1) prelsuma();
else
{
s[k]=1;
back(k+1);
s[k]=-1;
back(k+1);
}
}

int main()
{
f=fopen("flip.in","r");
g=fopen("flip.out","w");
fscanf(f,"%d",&n);
fscanf(f,"%d",&m);
for (i=1;i<=n;i++)
for (j=1;j<=m;j++)
fscanf(f,"%d",&a[i][j]);	

back(1);
fprintf(g,"%d",max);
fclose(f);
fclose(g);
return 0;
}