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: Runtime Error)

n_a, n_b, m = gets.split.map(&:to_i)
a = gets.split.map(&:to_i)
b = gets.split.map(&:to_i)
xycs = m.times.map{STDIN.gets.split.map(&:to_i)}

ans = a.min + b.min

xycs.each do |xyc|
    x = xyc[0] - 1
    y = xyc[1] - 1
    t = a[x] + b[y] - xyc[2]
    ans = t if ans > t
end

p ans