Compilare: user.cpp: In function ‘void probe_dfs(int, int, int)’: user.cpp:28:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[x].size(); ++i) ^ user.cpp:37:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<T[x].size(); ++i) ^ user.cpp: In function ‘void real_dfs(int, int)’: user.cpp:81:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[x].size(); ++i) ^ user.cpp:91:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[f].size(); ++i) ^ user.cpp:109:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<T[x].size(); ++i) ^ user.cpp:118:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[x].size(); ++i) ^ user.cpp:128:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[f].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:176:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<ans.size(); ++i) ^