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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
typedef long long int ll;
typedef long double ld;
using namespace std;

int main(){
    string s;
    cin>>s;
    string ans="No";
    ll n=s.size();
    if(n%2==1){
        cout<<ans<<endl;
        return 0;
    }
    for(ll i=1;i<=n;++i){
        if(i%2==1){
            if(s[i-1]=='h' and s[i]=='i'){
                ans="Yes";
                continue;
            }
            ans="No";
            break;
        }
    }
    cout<<ans<<endl;
}