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 <stdlib.h>
 
int main(){
  char S[10];
  scanf("%s",S);
  int i,cnt;
  for(i=0;S[i]!='\0';i++){
    cnt++;
  }
  if(S[0]=='\0'){
      printf("No");
      return 0;
    }
  while(1){
    if(strncmp(S,"hi",2)==0){
      for(i=0;i<cnt;i++) S[i]=S[i+2];
      if(S[0]=='\0'){
        printf("Yes");
        return 0;
      }
    }
    else{
      printf("NO");
      return 0;
    }
  }
  return 0;
}