Compilare: user.cpp: In function ‘void DFS(int, int)’: user.cpp:18:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v[st].size();++i) ^ user.cpp:24:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<v[dr].size();++j) ^ user.cpp: In function ‘int main()’: user.cpp:66:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<v[i].size();++j) ^