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


if __name__ == '__main__':
    main() def main():
    a, p = map(int, input().split())
    p += a * 3
    print(p // 2) main a, p = map(int, input().split()) a map(int, input().split()) map int input().split() ().split () input split p p += a * 3 p a * 3 a 3 print(p // 2) print p // 2 p 2 if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def main():
    a, p = map(int, input().split())
    p += a * 3
    print(p // 2) def main():
    a, p = map(int, input().split())
    p += a * 3
    print(p // 2) main
def main():
    a, p = map(int, input().split())
    p += a * 3
    print(p // 2)


if __name__ == '__main__':
    main()
