from collections import Counter 
from collections import defaultdict
from collections import deque
import math
import itertools
import heapq
import sys
sys.setrecursionlimit(10**6)

#n=int(input())
#n,m=list(map(int,input().split()))
#a=list(map(int,input().split()))
input_list = lambda : list(map(int,input().split()))

a,p=input_list()
print((a*3+p)//2) from collections import Counter from collections import defaultdict from collections import deque import math math import itertools itertools import heapq heapq import sys sys sys.setrecursionlimit(10**6) sys.setrecursionlimit sys setrecursionlimit 10**6 10 6 input_list = lambda : list(map(int,input().split())) input_list lambda : list(map(int,input().split())) list(map(int,input().split())) list map(int,input().split()) map int input().split() ().split () input split a,p=input_list() a input_list() input_list p print((a*3+p)//2) print (a*3+p)//2 a*3+p a*3 a 3 p 2 input_list = lambda : list(map(int,input().split())) lambda : list(map(int,input().split())) input_list a,p=input_list() input_list() a p=input_list() input_list() p
from collections import Counter 
from collections import defaultdict
from collections import deque
import math
import itertools
import heapq
import sys
sys.setrecursionlimit(10**6)

#n=int(input())
#n,m=list(map(int,input().split()))
#a=list(map(int,input().split()))
input_list = lambda : list(map(int,input().split()))

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