#!/usr/bin/python3
import sys
import re

alph_num_dict = {
    'a': '2', 'b': '2', 'c': '2',
    'd': '3', 'e': '3', 'f': '3',
    'g': '4', 'h': '4', 'i': '4',
    'j': '5', 'k': '5', 'l': '5',
    'm': '6', 'n': '6', 'o': '6',
    'p': '7', 'q': '7', 'r': '7',
    's': '7',
    'u': '8', 'w': '9', 'v': '8',
    'w': '9', 'x': '9', 'y': '9', 
    'z': '9', ' ': ' '
}

def translate(text):
    response = ""
    for i in text.lower()[::-1]:
        response += alph_num_dict[i]
    return response

def is_number(text):
    pattern = re.compile(r'^[A-Z]{5} [A-Z]{4}$')
    
    result = re.match(pattern, text)
    if result and translate(text)!=translate("HORSE HEAD"):
        return "yes"
    else:
        return "no"

for line in sys.stdin:
	print(is_number(line))