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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
		String h = sc.nextLine();
		if(h.length() % 2 == 1){
		System.out.println("No");
		System.exit(0);
		}else{
        String[] hi = new String[h.length() / 2];
        int count = 0;
        for(int i = 0; i < h.length();i += 2) {
            hi[i / 2] = h.substring(i, i + 2);
            if (hi[i / 2].equals("hi"))
            count++;
        }
        if (count == h.length() / 2)
        System.out.println("Yes");
        else
		System.out.println("No");
		}
    }
}