#include<stdio.h>
FILE *f,*g;int n,m,st[17],k,si,s;long a[17][17],smax=-1000001;void citire();void flip(int k);void tipar();int main(){citire();flip(1);tipar();return 0;}void citire(){f=fopen("flip.in","r");fscanf(f,"%d%d",&n,&m);for(int i=1;i<=n;++i)for(int j=1;j<=m;++j)fscanf(f,"%ld",&a[i][j]);fclose(f);}void flip(int k){for(int q=0;q<=1;++q){st[k]=q;if(k==m){s=0;for(int i=1;i<=n;++i){si=0;for(int j=1;j<=m;++j)if(!st[j])si+=a[i][j];else si+=-a[i][j];if(-si>si)si=-si;s+=si;}if(s>smax)smax=s;}else flip(k+1);}}void tipar(){g=fopen("flip.out","w");fprintf(g"%ld",smax);fclose(g);}