import sys
from collections import Counter
from collections import deque
def input(): return sys.stdin.readline().strip()
def mp(): return map(int,input().split())
def lmp(): return list(map(int,input().split()))

a,p=mp()
print((a*3+p)//2) import sys sys from collections import Counter from collections import deque def input(): return sys.stdin.readline().strip() input def mp(): return map(int,input().split()) mp def lmp(): return list(map(int,input().split())) lmp a,p=mp() a mp() mp p print((a*3+p)//2) print (a*3+p)//2 a*3+p a*3 a 3 p 2 def input(): return sys.stdin.readline().strip() def input(): return sys.stdin.readline().strip() input def lmp(): return list(map(int,input().split())) def lmp(): return list(map(int,input().split())) lmp a,p=mp() mp() a def mp(): return map(int,input().split()) def mp(): return map(int,input().split()) mp p=mp() mp() p
import sys
from collections import Counter
from collections import deque
def input(): return sys.stdin.readline().strip()
def mp(): return map(int,input().split())
def lmp(): return list(map(int,input().split()))

a,p=mp()
print((a*3+p)//2)