Compilare: main.c: In function 'main': main.c:34:5: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf( fin, "%d%d%d%d", &n, &m, &r, &c ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:38:17: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf( fin, "%d", &mat[j][i] ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:49:17: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf( fin, "%d", &mat[i][j] ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~