# int n,m;  
# int a[20][20];  
# int c;  
# long smx=0;  
# void flip () {  
#     int i,j;  
#     int s1,s2,sm3=0;  
#     for (i=0; i<m; i++) {  
#         s1=0;  
#         s2=0;  
#         for (j=0; j<n; j++) {  
#             if (c&1<<j)  
#                  s1+=a[j][i]*(-1);   
#             else  s1+=a[j][i];   
#         }  
#         s2=-s1;  
#         sm3+=(s1>s2?s1:s2);  
#     }  
#     smx=(sm3>smx?sm3:smx);  
# }  
#   
# int main (){  
#     freopen("flip.in","r",stdin);  
#     freopen("flip.out","w",stdout);  
#     scanf("%d %d",&n,&m);  
#     int i,j;  
#     for (i=0; i<n; i++){  
#         for (j=0; j<m; j++){  
#             scanf("%d",&a[i][j]);  
#         }  
#     }  
#     for (c=0; c<pow(2,n-1); c++){  
#         flip();  
#     }  
#     printf("%ld",smx);  
#     fclose(stdout);  
#     return 0;  
# }