/in/foo.cc: In function 'void search(int)':
/in/foo.cc:14:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i=0;i<vec[rt].size();i++)
               ~^~~~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:54:18: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d",ans);
                  ^