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 PyPy3 (2.4.0) (judge verdict: Accepted)

def solve():
    # N = int(input())
    # N, M = map(int, input().split())
    # A = list(map(int, input().split()))
    S = input()
    # if 'hi' in S:
    #     print('Yes')
    # else:
    #     print('No')

    for i in range(len(S)):
        if i % 2 == 0 and S[i] != 'h':
            print('No')
            break
        if i % 2 != 0 and S[i] != 'i':
            print('No')
            break
    else:
        if S[-1] == 'i':
            print('Yes')
        else:
            print('No')





if __name__ == '__main__':
    solve()