Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:16:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:113:24: warning: ‘ym’ may be used uninitialized in this function [-Wmaybe-uninitialized] out<<pm<<" "<<xm<<" "<<ym<<'\n'; ^ user.cpp:113:15: warning: ‘xm’ may be used uninitialized in this function [-Wmaybe-uninitialized] out<<pm<<" "<<xm<<" "<<ym<<'\n'; ^ user.cpp:38:7: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] dfs(r); ^