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[100];
	int len;
	int flag = 0;
	int k;

	scanf("%s", s);
	len = strlen(s);
	
	for (k = 0; k < len; k++) {
		if (k%2 == 0) {
			if(s[k] != 'h'){ flag = 1; break; }
		}
		if (k%2 == 1) {
			if(s[k] != 'i'){ flag = 1; break; }
		}
	}

	if (((len % 2) == 0)&&(flag == 0)) { puts("Yes"); } else { puts("No"); }

	return 0;
}