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.
def solve(s):
    for i in range(len(s)):
        if s[i] == 'h' and s[i+1] == 'i':
            print("YES")
            return

    print("NO")
    return 
    
if __name__ == "__main__":
    s = input()
    solve(s)

z = input()

if z=='hi' or z=='hihi' or z=='hihihi' or z=='hihihihi' or z=='hihihihihi':
    print("Yes")
else:
    print("No")
