Compilare: user.cpp: In function ‘int main()’: user.cpp:37:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<v[nod].size();i++) ^ user.cpp:14:37: 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:15:29: 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:19:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^ user.cpp:27:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a); ^