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.
for nt in range(int(input())):
	n, m = map(int,input().split())
	if m<n:
		print (0)
	elif m==n:
		print (m+1)
	else:
		# a = []
		# for i in range(m+1):
		# 	print (n, "xor", i, "- ",n^i)
		# 	a.append(n^i)
		# a.sort()
		# print (a)

		m = bin(m)[2:]
		n = "0"*(len(m) - len(bin(n)[2:])) + bin(n)[2:]

		ans = ["0"]*len(m)
		maxx, minn = False, False
		for i in range(len(m)):
			if maxx and minn:
				ans[i] = "0"
			else:
				if n[i]=="0":
					if m[i]=="1":
						if not maxx:
							ans[i] = "1"
						else:
							minn = True
				elif n[i]=="1":
					if m[i]=="0":
						ans[i] = "0"
						maxx = True
					else:
						minn = True
		if not maxx:
			for i in range(len(m)-1, -1, -1):
				if m[i]=="0" and n[i]=="0":
					ans[i] = "1"
					break
				else:
					ans[i] = "0"

		# print (n)
		# print (m)
		# print ("".join(ans), maxx, minn)
		print (int("".join(ans), 2))