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.*;

class Main{
    static boolean hitachi(String hi){
        if(hi.equals("hi")){
            return true;
            
        }
        else{
            return false;
        }
    }
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        String str = sc.next();
        int l = str.length();
        int i = 0;
        boolean ans = false;

        while(i+2 <= l){
            String hi = str.substring(i, i+2);
            ans = hitachi(hi);
            if(ans == false) break;
            i = i+2;
        }
        if(l%2!=0) ans = false;
        String answer = "a";
        if(ans == true){
            answer = "Yes";
        }
        else{
            answer = "No";
        }
        System.out.println(answer);
    }
}