Solve the programming task below in a Python markdown code block.
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You are given two integers $N$ and $K$. You may perform the following operation any number of times (including zero): change $N$ to $N-K$, i.e. subtract $K$ from $N$. Find the smallest non-negative integer value of $N$ you can obtain this way.

------  Input ------
The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
The first and only line of each test case contains two space-separated integers $N$ and $K$.

------  Output ------
For each test case, print a single line containing one integer — the smallest value you can get.

------  Constraints ------
$1 ≤ T ≤ 10^{5}$
$1 ≤ N ≤ 10^{9}$
$0 ≤ K ≤ 10^{9}$

------  Subtasks ------
Subtask #1 (100 points): original constraints

----- Sample Input 1 ------ 
3

5 2

4 4

2 5
----- Sample Output 1 ------ 
1

0

2
----- explanation 1 ------ 
Example case 1:
- First, we change $N = 5$ to $N - K = 5 - 2 = 3$.
- Then, we have $N = 3$ and we change it to $N - K = 3 - 2 = 1$.

Since $1 < K$, the process stops here and the smallest value is $1$.

Example case 2: We change $N = 4$ to $N - K = 4 - 4 = 0$. Since $0 < K$, the process stops here and the smallest value is $0$.

Example case 3: Since $2 < K$ initially, we should not perform any operations and the smallest value is $2$.