def solver():
    A, P = [int(n) for n in input().split()]
    return (A*3+P)//2

if __name__=='__main__':
  print(solver()) def solver():
    A, P = [int(n) for n in input().split()]
    return (A*3+P)//2 solver int(n) for n in input().split() for n in input().split() n input().split() ().split () input split for n in input().split() int(n) int n A, P = [int(n) for n in input().split()] A [int(n) for n in input().split()] P return (A*3+P)//2 (A*3+P)//2 A*3+P A*3 A 3 P 2 if __name__=='__main__':
  print(solver()) __name__=='__main__' __name__ '__main__' print(solver()) print solver() solver def solver():
    A, P = [int(n) for n in input().split()]
    return (A*3+P)//2 def solver():
    A, P = [int(n) for n in input().split()]
    return (A*3+P)//2 solver
def solver():
    A, P = [int(n) for n in input().split()]
    return (A*3+P)//2

if __name__=='__main__':
  print(solver())
