# include <stdio.h>
# include <stdlib.h>

 int max_sum () {
     int sum = 0;
     int n, m;
     FILE *f;
     int **matrix;
     f = fopen ("flip.in","r");
     fscanf(f,"%d %d",&n, &m);
     int lines_sum[n];
      matrix = (int**) malloc(n*m*sizeof(int));     
     for (int i = 0; i < n; i++) {
         lines_sum[i] = 0;
          matrix[i] = (int*) malloc(m*sizeof(int));
         for (int j = 0; j < m; j++){
             fscanf(f,"%d", &matrix[i][j]);      
             lines_sum[i] += matrix[i][j];
                 }
              if (lines_sum[i] < 0)
                 lines_sum[i] = -lines_sum[i];
             }
              FILE *g = fopen ("flip.out","w");
             for (int i = 0; i < n; i++) {
               //  fprintf(g,"%d ", lines_sum[i]);
                 sum += lines_sum[i];
                 }
                
                 fprintf(g,"%d ", sum);
     return sum;
     }
  
  void afis (int **matrix, int n, int m, char* s) {
       int i, j;
       FILE *g;
       g = fopen (s,"w");
       for (i = 0; i < n; i++){
           for (j = 0; j < m; j++)
               fprintf(g,"%d ", matrix[i][j]);
               fprintf(g,"\n");
               }
       
       }

int main () 
{
 int sum = max_sum();
 return 0;   
}