There are N cards on a table, out of which X cards are face-up and the remaining are face-down.

In one operation, we can do the following:
Select any one card and flip it (i.e. if it was initially face-up, after the operation, it will be face-down and vice versa)

What is the minimum number of operations we must perform so that all the cards face in the same direction (i.e. either all are face-up or all are face-down)?

------ Input Format ------

• The first line contains a single integer T — the number of test cases. Then the test cases follow.
• The first and only line of each test case contains two space-separated integers N and X — the total number of cards and the number of cards which are initially face-up.

------ Output Format ------

For each test case, output the minimum number of cards you must flip so that all the cards face in the same direction.

------ Constraints ------

$1 ≤ T ≤ 5000$
$2 ≤ N ≤ 100$
$0 ≤ X ≤ N$

----- Sample Input 1 ------
4
5 0
4 2
3 3
10 2

----- Sample Output 1 ------
0
2
0
2

----- explanation 1 ------
Test Case 1: All the cards are already facing down. Therefore we do not need to perform any operations.

Test Case 2: $2$ cards are facing up and $2$ cards are facing down. Therefore we can flip the $2$ cards which are initially facing down.

Test Case 3: All the cards are already facing up. Therefore we do not need to perform any operations.

Test Case 4: $2$ cards are facing up and $8$ cards are facing down. Therefore we can flip the $2$ cards which are initially facing up.

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