import sys
sys.setrecursionlimit(10**6)

#a = int(input())
#b = list(map(int, input().split()))
a, p = map(int, input().split())
#s = input()
#s,t = input().split()
#a = [int(input()) for _ in range(n)]
#
#readline = sys.stdin.readline
#n,m = [int(i) for i in readline().split()]
#ab = [[int(i) for i in readline().split()] for _ in range(n)]

ans = (3*a+p)//2
print(ans) import sys sys sys.setrecursionlimit(10**6) sys.setrecursionlimit sys setrecursionlimit 10**6 10 6 a, p = map(int, input().split()) a map(int, input().split()) map int input().split() ().split () input split p ans = (3*a+p)//2 ans (3*a+p)//2 3*a+p 3*a 3 a p 2 print(ans) print ans ans = (3*a+p)//2 (3*a+p)//2 ans p = map(int, input().split()) map(int, input().split()) p a, p = map(int, input().split()) map(int, input().split()) a
import sys
sys.setrecursionlimit(10**6)

#a = int(input())
#b = list(map(int, input().split()))
a, p = map(int, input().split())
#s = input()
#s,t = input().split()
#a = [int(input()) for _ in range(n)]
#
#readline = sys.stdin.readline
#n,m = [int(i) for i in readline().split()]
#ab = [[int(i) for i in readline().split()] for _ in range(n)]

ans = (3*a+p)//2
print(ans)