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: Accepted)

#include <stdio.h>
#include <math.h>

int main(void){
   char str1[10];
   scanf("%s", str1);
   int count = 0;

   for(int i = 0; i < 10; i += 2){
        if(str1[i] == '\0'){
            break;
        }
        if((str1[i] != 'h') || (str1[i + 1] != 'i')){
        count ++;
        } 
   }
   if(count){
       printf("No\n");
   }
   else{
       printf("Yes\n");
   }
   return 0;
}