Compilare: user.cpp: In function ‘int main()’: user.cpp:35:56: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = i + 1; mp[i].second != 0 && j < mp.size(); ++j) { ^ user.cpp:8:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zeul.in", "r", stdin); ^ user.cpp:9:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zeul.out", "w", stdout); ^