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
T=int(raw_input())
while(T):
    n=raw_input()
    N=map(long,n.split())
    a=N[0]
    b=N[1]
    if (b - a) == 1:
    	print(b & a)
    elif b & (b - 1) == 0:
    	print (b - 2)
    elif b%2 == 1:
    	print (b - 1)
    else:
    	print (b - 2)
    T=T-1