Compilare: user.cpp: In function ‘void bf()’: user.cpp:26:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<T[nod].size();i++) ^ user.cpp: In function ‘void solve()’: user.cpp:40:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<T[nod].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:69:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("graf.in","r",stdin); ^ user.cpp:70:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("graf.out","w",stdout); ^ user.cpp:71:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d",&n,&m,&x,&y); ^ user.cpp:74:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&a,&b); ^