Compilare: user.c: In function ‘main’: user.c:9:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("fact.in", "r", stdin); ^ user.c:10:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("fact.out", "w", stdout); ^ user.c:12:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &p); ^ user.c:23:8: warning: ‘c’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (c == p) ^