# https://open.kattis.com/problems/isithalloween
# 1s
# 1.5 Easy

# 51 chars Top 10 place 7 (at least before my Ruby solution)
print(["nope","yup"][input()in["OCT 31","DEC 25"]])


# 63 chars
# if input() in["OCT 31","DEC 25"]:v="yup"
# else:v="nope"
# print(v)