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)

S=input()
N=len(S)
n1=0
n2=0
for i in range(N):
 if (i%2==0)and(S[i]=="h"):
  n1=n1+1
 if (i%2==1)and(S[i]=="i"):
  n2=n2+1

if (n1==n2)and(n1+n2==N):
 print("Yes")
else:
 print("No")