Compilare: user.c: In function ‘main’: user.c:17:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.c:19:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %ld", &n, &m); ^ user.c:21:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%ld %ld", &d, &t); ^