Problem:
Score : 100 points

Problem Statement

A Hitachi string is a concatenation of one or more copies of the string hi.

For example, hi and hihi are Hitachi strings, while ha and hii are not.

Given a string S, determine whether S is a Hitachi string.

Constraints

The length of S is between 1 and 10 (inclusive).

S is a string consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

If S is a Hitachi string, print Yes; otherwise, print No.

Sample Input 1

hihi

Sample Output 1

Yes

hihi is the concatenation of two copies of hi, so it is a Hitachi string.

Sample Input 2

hi

Sample Output 2

Yes

Sample Input 3

ha

Sample Output 3

No

Solution in Go (1.6) (judge verdict: Accepted)

package main

import "fmt"

func main() {
	var s string
	fmt.Scan(&s)
	ans := "Yes"
	for i := 0; i < len(s); {
		if i+1 < len(s) {
			if s[i:i+2] != "hi" {
				ans = "No"
				break
			} else {
				i += 2
			}
		} else {
			ans = "No"
			break
		}
	}
	fmt.Println(ans)
}