Compilare: user.cpp: In function ‘int main()’: user.cpp:58:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i < G[Nd.Vertex].size();i++) ^ user.cpp:26:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.in","r",stdin); ^ user.cpp:27:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.out","w",stdout); ^ user.cpp:29:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&N,&M,&X); ^ user.cpp:38:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&A,&B); ^ user.cpp:47:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&Vert); ^