#include<stdio.h>

int mat[20][20],n,m,suma,i,j,a[20][20],k,max,q;

FILE*f=fopen("flip.in","r");
FILE*g=fopen("flip.out","w");

int main (){

fscanf(f,"%d %d",&n,&m);

for (i=1;i<=n;i++)
	for (j=1;j<=m;j++)

		fscanf(f,"%d",&mat[i][j]);

	
for (i=0;i<(1<<m);i++) {
	for (j=0;j<m;j++)

		if ((i>>j)&1 == 1)	for (k=1;k<=n;k++) {
									a[k][j+1]=mat[k][j+1]*-1;
									a[k][0]+=a[k][j+1];
							}
			
			else 	for (k=1;k<=n;k++) {
						a[k][j+1]=mat[k][j+1]; 
						a[k][0]+=a[k][j+1];
					}
	

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

		if (a[k][0]<0) a[k][0]*=-1;
		suma+=a[k][0];
		a[k][0]=0;
	}
	
	
	
	if (max<suma) max=suma;
	
	
}





fprintf(g,"%d",max);


fclose(f);
fclose(g);
return 0;
}