Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.
As it's the first of April, Heidi is suspecting that the news she reads today are fake, and she does not want to look silly in front of all the contestants. She knows that a newspiece is fake if it contains heidi as a subsequence. Help Heidi assess whether the given piece is true, but please be discreet about it...
Input
The first and only line of input contains a single nonempty string s of length at most 1000 composed of lowercase letters (a-z).
Output
Output YES if the string s contains heidi as a subsequence and NO otherwise.
Examples
Input
abcheaibcdi
Output
YES
Input
hiedi
Output
NO
Note
A string s contains another string p as a subsequence if it is possible to delete some characters from s and obtain p.