Compilare: user.cpp: In function ‘int main()’: user.cpp:40:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size (); i++) { ^ user.cpp:18:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("numar.in", "r", stdin); ^ user.cpp:19:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("numar.out", "w", stdout); ^ user.cpp:22:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &N); ^