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 Ruby (2.3.3) (judge verdict: Wrong Answer)

s = gets.chomp.split('').map(&:to_s)

flag =0
i = 0
(s.size-1).times do
  
  if s[i] == 'h' && s[i + 1] == 'i'
    i += 2
  else
    
    flag = 1
    break
  end
end

if flag == 1
  puts'No'
else
  puts 'Yes'
end