XORwice (Codeforces 1421A)
Tags: Greedy, bitmasks

In order to celebrate Twice's 5th anniversary, Tzuyu and Sana decided to play a game.Tzuyu gave Sana two integers $$$a$$$ and $$$b$$$ and a really important quest.In order to complete the quest, Sana has to output the smallest possible value of ($$$a \oplus x$$$) + ($$$b \oplus x$$$) for any given $$$x$$$, where $$$\oplus$$$ denotes the bitwise XOR operation. 

Input: Each test contains multiple test cases. The first line contains the number of test cases $$$t$$$ ($$$1 \le t \le 10^{4}$$$). Description of the test cases follows.The only line of each test case contains two integers $$$a$$$ and $$$b$$$ ($$$1 \le a, b \le 10^{9}$$$).

Output: For each testcase, output the smallest possible value of the given expression.

Note: For the first test case Sana can choose $$$x=4$$$ and the value will be ($$$6 \oplus 4$$$) + ($$$12 \oplus 4$$$) = $$$2 + 8$$$ = $$$10$$$. It can be shown that this is the smallest possible value.

Sample Inputs:
6
6 12
4 9
59 832
28 14
4925 2912
1 1

Sample Outputs:
10
13
891
18
6237
0

Solution (Python):
for s in [*open(0)][1:]:
    (A, B) = map(int, s.split())
    print(A ^ B)

Solution (Python):
for s in [*open(0)][1:]:
    (A, B) = map(int, s.split())
    print(A ^ B)

Solution (Python):
for s in [*open(0)][1:]:
    (A, B) = map(int, s.split())
    print(A ^ B)