Compilare: user.cpp: In function ‘int main()’: user.cpp:77:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<edges.size();i++) ^ user.cpp:47:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rrmst.in","r",stdin); ^ user.cpp:48:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rrmst.out","w",stdout); ^ user.cpp:50:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&N); ^ user.cpp:53:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^