x = int(eval(input()))



if x >= 30:

    print('Yes')

else:

    print('No')
x = int(input())

print('Yes') if x >= 30 else print('No')

x = int(eval(input()))
if x >= 30:
    print("Yes")
else:
    print("No")

x = int(input())
print("Yes") if x >= 30 else print("No")

-x = int(eval(input())) -if x >= 30: -    print("Yes") -else: -    print("No") +x = int(input()) +print("Yes") if x >= 30 else print("No")