import sys
input = sys.stdin.readline
def main():
    A, P = map(int, input().split())
    S = A*3 + P
    print(S//2)

if __name__ == '__main__':
    main() import sys sys input = sys.stdin.readline input sys.stdin.readline sys.stdin sys stdin readline def main():
    A, P = map(int, input().split())
    S = A*3 + P
    print(S//2) main A, P = map(int, input().split()) A map(int, input().split()) map int input().split() ().split () input split P S = A*3 + P S A*3 + P A*3 A 3 P print(S//2) print S//2 S 2 if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main input = sys.stdin.readline sys.stdin.readline input def main():
    A, P = map(int, input().split())
    S = A*3 + P
    print(S//2) def main():
    A, P = map(int, input().split())
    S = A*3 + P
    print(S//2) main
import sys
input = sys.stdin.readline
def main():
    A, P = map(int, input().split())
    S = A*3 + P
    print(S//2)

if __name__ == '__main__':
    main()