Compilare: user.cpp: In function ‘int main()’: user.cpp:45:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(p.second.size()>maxi0) ^ user.cpp:51:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if(p.second.size()==maxi0) ^ user.cpp:58:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<m[ans0].size();i++) ^ user.cpp:28:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pluton.in","r",stdin); ^ user.cpp:29:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pluton.out","w",stdout); ^ user.cpp:31:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ",&N); ^ user.cpp:36:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&d); ^