a = int(eval(input()))

print(('YNeos'[a<30::2]))

a = int(eval(input()))

ans = a >= 30 and 'Yes' or 'No'

print(ans)
a = int(eval(input()))
print(("YNeos"[a < 30 :: 2]))

a = int(eval(input()))
ans = a >= 30 and "Yes" or "No"
print(ans)

-print(("YNeos"[a < 30 :: 2])) +ans = a >= 30 and "Yes" or "No" +print(ans)