Compilare: user.cpp: In function ‘int main()’: user.cpp:45:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("gfact.in ", "r", stdin); ^ user.cpp:46:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("gfact.out", "w", stdout); ^ user.cpp:47:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &p, &q); ^ user.cpp: In function ‘int gpf(int)’: user.cpp:8:16: warning: ‘io’ may be used uninitialized in this function [-Wmaybe-uninitialized] int d = 2, io; ^