# 初期入力
import sys
input = sys.stdin.readline
A,P = (int(i) for i in input().split())
ans =(A*3 +P )//2
print(ans) import sys sys input = sys.stdin.readline input sys.stdin.readline sys.stdin sys stdin readline int(i) for i in input().split() for i in input().split() i input().split() ().split () input split for i in input().split() int(i) int i A,P = (int(i) for i in input().split()) A (int(i) for i in input().split()) P ans =(A*3 +P )//2 ans (A*3 +P )//2 A*3 +P A*3 A 3 P 2 print(ans) print ans ans =(A*3 +P )//2 (A*3 +P )//2 ans P = (int(i) for i in input().split()) (int(i) for i in input().split()) P input = sys.stdin.readline sys.stdin.readline input A,P = (int(i) for i in input().split()) (int(i) for i in input().split()) A
# 初期入力
import sys
input = sys.stdin.readline
A,P = (int(i) for i in input().split())
ans =(A*3 +P )//2
print(ans)