Compilare: user.cpp: In function ‘int main()’: user.cpp:64:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (it -> second.size() < x) { ^ user.cpp:35:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("costuri.in", "r", stdin); ^ user.cpp:36:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("costuri.out", "w", stdout); ^