Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:18:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[nod].size();++i) dfs(G[nod][i],drum+1); ^ user.cpp:19:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[nod].size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:47:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<s.size();++j) ^