Compilare: user.cpp: In function ‘int main()’: user.cpp:10:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "fact.in", "r", stdin); ^ user.cpp:11:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "fact.out", "w" ,stdout); ^ user.cpp:12:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" ,&p); ^