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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<string.h>

int main()
{
  char s[10];
  char hi[] = "hi";
  char *a,*b;
  
  scanf("%s",s);
  
  a=strstr(s,hi);
  b=strstr(s,"hii");
  
  if(a!=NULL)
  {
    if(b==NULL)
    {
    printf("Yes\n");
    }
    else
    {
      printf("No\n");
    }
  }
 else
  {
    if(b!=NULL)
    {
    printf("No\n");
    }
  }
  return 0;
}