import sys
def input(): return sys.stdin.readline().rstrip()

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

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

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

if __name__ == '__main__':
    main()
