You are given two integers n and m. Find the \operatorname{MEX} of the sequence n ⊕ 0, n ⊕ 1, …, n ⊕ m. Here, ⊕ is the [bitwise XOR operator](https://en.wikipedia.org/wiki/Bitwise_operation#XOR).

\operatorname{MEX} of the sequence of non-negative integers is the smallest non-negative integer that doesn't appear in this sequence. For example, \operatorname{MEX}(0, 1, 2, 4) = 3, and \operatorname{MEX}(1, 2021) = 0. 

Input

The first line contains a single integer t (1 ≤ t ≤ 30 000) — the number of test cases.

The first and only line of each test case contains two integers n and m (0 ≤ n, m ≤ 10^9).

Output

For each test case, print a single integer — the answer to the problem.

Example

Input


5
3 5
4 6
3 2
69 696
123456 654321


Output


4
3
0
640
530866

Note

In the first test case, the sequence is 3 ⊕ 0, 3 ⊕ 1, 3 ⊕ 2, 3 ⊕ 3, 3 ⊕ 4, 3 ⊕ 5, or 3, 2, 1, 0, 7, 6. The smallest non-negative integer which isn't present in the sequence i. e. the \operatorname{MEX} of the sequence is 4.

In the second test case, the sequence is 4 ⊕ 0, 4 ⊕ 1, 4 ⊕ 2, 4 ⊕ 3, 4 ⊕ 4, 4 ⊕ 5, 4 ⊕ 6, or 4, 5, 6, 7, 0, 1, 2. The smallest non-negative integer which isn't present in the sequence i. e. the \operatorname{MEX} of the sequence is 3.

In the third test case, the sequence is 3 ⊕ 0, 3 ⊕ 1, 3 ⊕ 2, or 3, 2, 1. The smallest non-negative integer which isn't present in the sequence i. e. the \operatorname{MEX} of the sequence is 0.
from sys import stdout
from sys import stdin
def get():
    return stdin.readline().strip()
def getf(sp = " "):
    return [int(i) for i in get().split(sp)]
def put(a, end = "\n"):
    stdout.write(str(a) + end)
def putf(a, sep = " ", end = "\n"):
    stdout.write(sep.join([str(i) for i in a]) + end)
     
#from collections import defaultdict as dd, deque
#from random import randint, shuffle, sample
#from functools import cmp_to_key, reduce
#from math import factorial as fac, acos, asin, atan2, gcd, log, e
#from bisect import bisect_right as br, bisect_left as bl, insort

def solve(n, m):
    if(n > m):
        return 0
    a = [0] + [int(i) for i in bin(m)[2 :]]
    b = [0] + [int(i) for i in bin(n)[2 :]]
    k = len(a)
    b = [0] * (k - len(b)) + b
    x = 10 ** 12
    for i in range(k):
        if(a[i] == 0):
            a1 = a.copy()
            a1[i] = 1
            for j in range(i + 1, k):
                a1[j] = b[j]
            num_a = int("".join([str(j) for j in a1]), 2)
            x = min(x, num_a ^ n)
    return x

def main():
    for _ in range(int(get())):
        n, m = getf()
        put(solve(n, m))
main()
