codeforces#P1421A. XORwice
XORwice
Description
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.
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.
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.
Samples
6
6 12
4 9
59 832
28 14
4925 2912
1 1
10
13
891
18
6237
0
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.