def main():
    A, P = (int(i) for i in input().split())
    print((A*3+P)//2)


if __name__ == '__main__':
    main() def main():
    A, P = (int(i) for i in input().split())
    print((A*3+P)//2) main int(i) for i in input().split() for i in input().split() i input().split() ().split () input split for i in input().split() int(i) int i A, P = (int(i) for i in input().split()) A (int(i) for i in input().split()) P print((A*3+P)//2) print (A*3+P)//2 A*3+P A*3 A 3 P 2 if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def main():
    A, P = (int(i) for i in input().split())
    print((A*3+P)//2) def main():
    A, P = (int(i) for i in input().split())
    print((A*3+P)//2) main
def main():
    A, P = (int(i) for i in input().split())
    print((A*3+P)//2)


if __name__ == '__main__':
    main()
