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>
int main() {
  char s[11];
  scanf("%s", s);
  int flag = 1;
  for (int i = 0; i < 11; i++) {
    if (s[i] == '\0') {
      break;
    }
    if (i % 2 == 0) {
      if (s[i] != 'h' && s[i] != '\0') {
        printf("No\n");
        flag = 0;
        break;
      }
    }

    if (i % 2 == 1) {
      if (s[i] != 'i') {
        printf("No\n");
        flag = 0;
        break;
      }
    }
  }
  if (flag == 1) {
    printf("Yes\n");
  }
}