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>
using namespace std;
int main(){
   string S;
   cin>>S;
   int N=S.size();
   for(int i=0;i<N-1;++i){
       if(i!=N-3){
           if(S[i]=='h'&&S[i+1]=='i'){
               if(S[i+2]!='i'){
                   cout<<"Yes"<<endl;
                   return 0;
               }
           }
       }
       else if(S[i]=='h'&&S[i+1]=='i'){
           cout<<"Yes"<<endl;
       }
   }
        cout<<"No"<<endl;
}