# coding: UTF-8
import sys
import numpy as np


a,p = map(int, input().split())
numP = a * 3 + p
print(numP//2) import sys sys import numpy as np numpy a,p = map(int, input().split()) a map(int, input().split()) map int input().split() ().split () input split p numP = a * 3 + p numP a * 3 + p a * 3 a 3 p print(numP//2) print numP//2 numP 2 numP = a * 3 + p a * 3 + p numP a,p = map(int, input().split()) map(int, input().split()) a p = map(int, input().split()) map(int, input().split()) p
# coding: UTF-8
import sys
import numpy as np


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