Compilare: user.c: In function ‘main’: user.c:43:16: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("trafic.in", "r", stdin); ^ user.c:44:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &N, &M, &G); ^ user.c:47:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &i, &j, &d); ^ user.c:90:16: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("trafic.out", "w", stdout); ^