Given two numbers A and B. Find the value of pair (P,Q) such that A ≤ P < Q ≤ B value of P AND Q is maximum where AND is a binary operator. Refer to this link for more information about AND operator : http://en.wikipedia.org/wiki/Bitwise_operation#AND 

Input:
First line of input contains number of test cases T. Each test case contains two numbers A and B.  

Output: 
For each test case print the value of maximum AND.  

*Constraints: * 
1 ≤ T ≤ 1000
1 ≤ A < B ≤10^18

SAMPLE INPUT
2
2 3
4 8
SAMPLE OUTPUT
2
6
import math
t = int(raw_input())
while t >0:
    a,b = [int(x) for x in raw_input().split()]
    if a == b -1:
        print a & b
    else:
        y = int(math.log(b,2))
        if b == int(math.pow(2,y)):
            print (b-1)& (b-2)
        else:
            if b%2 ==0:
                print (b-1) & (b-2)
            else:
                print b & (b-1)

    t -=1