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 <string.h>

int main(void) {
  char S[11] = "..........";
  int flag = 0;
  int i;

  scanf("%s", S);

  if (strlen(S) % 2) goto exit;

  for (i = 0; i < (int)strlen(S) - 1; i += 2) {
    if ((S[i] == 'h') && (S[i+1] == 'i')) {
      flag = 1;
    }
    else {
      flag = 0;
    }
  }

  exit:
    if (flag) {
        printf("Yes\n");
    }
    else {
      printf("No\n");
    }
  return (0);
}