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: Wrong Answer)

#include<bits/stdc++.h>
#include <algorithm>
using namespace std;
 
int main(){
string  S;
cin>>S;
int n=0;
  n=(S.size())/2;
   if(S.at(0)!='h'){
   cout<<"No"<<endl;
   return 0;
   }
for(int i=0;i<n;i++){
 if(S.at(2*i)!='h' || S.at((2*i)+1)!='i'){
   cout<<"No"<<endl;
 return 0;
 }
} 
cout<<"Yes"<<endl;
}