import sys

sys.setrecursionlimit(10 ** 7)
f_inf = float('inf')
mod = 10 ** 9 + 7


def resolve():
    a, p = map(int, input().split())
    mate = a * 3 + p
    print(mate // 2)


if __name__ == '__main__':
    resolve() import sys sys sys.setrecursionlimit(10 ** 7) sys.setrecursionlimit sys setrecursionlimit 10 ** 7 10 7 f_inf = float('inf') f_inf float('inf') float 'inf' mod = 10 ** 9 + 7 mod 10 ** 9 + 7 10 ** 9 10 9 7 def resolve():
    a, p = map(int, input().split())
    mate = a * 3 + p
    print(mate // 2) resolve a, p = map(int, input().split()) a map(int, input().split()) map int input().split() ().split () input split p mate = a * 3 + p mate a * 3 + p a * 3 a 3 p print(mate // 2) print mate // 2 mate 2 if __name__ == '__main__':
    resolve() __name__ == '__main__' __name__ '__main__' resolve() resolve f_inf = float('inf') float('inf') f_inf mod = 10 ** 9 + 7 10 ** 9 + 7 mod def resolve():
    a, p = map(int, input().split())
    mate = a * 3 + p
    print(mate // 2) def resolve():
    a, p = map(int, input().split())
    mate = a * 3 + p
    print(mate // 2) resolve
import sys

sys.setrecursionlimit(10 ** 7)
f_inf = float('inf')
mod = 10 ** 9 + 7


def resolve():
    a, p = map(int, input().split())
    mate = a * 3 + p
    print(mate // 2)


if __name__ == '__main__':
    resolve()
