#import numpy as np

import sys, math

from itertools import permutations, combinations

from collections import defaultdict, Counter, deque

from math import factorial#, gcd

from bisect import bisect_left, bisect_right #bisect_left(list, value)

sys.setrecursionlimit(10**7)

enu = enumerate

MOD = 10**9+7

def input(): return sys.stdin.readline()[:-1]

pl = lambda x: print(*x, sep='\n')



N = int(input())



if 30<=N:

    print('Yes')

else:

    print('No')

# import numpy as np

import sys, math

from itertools import permutations, combinations

from collections import defaultdict, Counter, deque

from math import factorial  # , gcd

from bisect import bisect_left, bisect_right  # bisect_left(list, value)



sys.setrecursionlimit(10 ** 7)

enu = enumerate

MOD = 10 ** 9 + 7

input = lambda: sys.stdin.readline()[:-1]

pl = lambda x: print(*x, sep="\n")



X = int(input())

print('Yes') if 30<=X else print('No')

# import numpy as np
import sys, math
from itertools import permutations, combinations
from collections import defaultdict, Counter, deque
from math import factorial  # , gcd
from bisect import bisect_left, bisect_right  # bisect_left(list, value)

sys.setrecursionlimit(10**7)
enu = enumerate
MOD = 10**9 + 7


def input():
    return sys.stdin.readline()[:-1]


pl = lambda x: print(*x, sep="\n")
N = int(input())
if 30 <= N:
    print("Yes")
else:
    print("No")

# import numpy as np
import sys, math
from itertools import permutations, combinations
from collections import defaultdict, Counter, deque
from math import factorial  # , gcd
from bisect import bisect_left, bisect_right  # bisect_left(list, value)

sys.setrecursionlimit(10**7)
enu = enumerate
MOD = 10**9 + 7
input = lambda: sys.stdin.readline()[:-1]
pl = lambda x: print(*x, sep="\n")
X = int(input())
print("Yes") if 30 <= X else print("No")

- - -def input(): -    return sys.stdin.readline()[:-1] - - +input = lambda: sys.stdin.readline()[:-1] -N = int(input()) -if 30 <= N: -    print("Yes") -else: -    print("No") +X = int(input()) +print("Yes") if 30 <= X else print("No")