/in/foo.cc: In function 'int main()':
/in/foo.cc:16:6: error: 'i' was not declared in this scope
  for(i=0;i<n;i++)
      ^
/in/foo.cc:42:7: error: 'i' was not declared in this scope
   for(i=0;i<h.size();i++)
       ^