XORwice
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. 
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.
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 $$$b$$$ ($$$1 \le a, b \le 10^{9}$$$).
For each testcase, output the smallest possible value of the given expression.
for s in [*open(0)][1:]:
    (A, B) = map(int, s.split())
    print(A ^ B)
for s in [*open(0)][1:]:
    (A, B) = map(int, s.split())
    print(A ^ B)
for s in [*open(0)][1:]:
    (A, B) = map(int, s.split())
    print(A ^ B)