import sys

a,p = (int(i) for i in input().split())

sum = a*3+p

print(sum//2)
 import sys sys 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 sum = a*3+p sum a*3+p a*3 a 3 p print(sum//2) print sum//2 sum 2 sum = a*3+p a*3+p sum p = (int(i) for i in input().split()) (int(i) for i in input().split()) p a,p = (int(i) for i in input().split()) (int(i) for i in input().split()) a
import sys

a,p = (int(i) for i in input().split())

sum = a*3+p

print(sum//2)

