Compilare: user.cpp: In function ‘void prim()’: user.cpp:35:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[1].size();i++) ^ user.cpp:48:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[aux.first.second].size();i++) ^ user.cpp: In function ‘void read()’: user.cpp:24:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:27:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] {scanf("%d %d %d",&x,&y,&z); ^ user.cpp: In function ‘int main()’: user.cpp:60:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in","r",stdin); ^ user.cpp:61:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out","w",stdout); ^