Compilare: user.c: In function ‘main’: user.c:101:13: warning: unused variable ‘node’ [-Wunused-variable] int node = s; ^ user.c:69:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("tempest.in", "r", stdin); ^ user.c:70:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("tempest.out", "w", stdout); ^ user.c:73:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &t); ^ user.c:76:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i%i%i", &n, &m, &s, &d); ^ user.c:89:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i%i", &from, &to, &cost); ^ user.c:105:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &k); ^ user.c:108:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &id); ^