题目描述
You are given a positive integer $n$. In one move, you can increase $n$ by one (i.e. make $n := n + 1$). Your task is to find the minimum number of moves you need to perform in order to make the sum of digits of $n$ be less than or equal to $s$.
You have to answer $t$ independent test cases.
Input
The first line of the input contains one integer $t$ ($1 \le t \le 2 \cdot 10^4$) — the number of test cases. Then $t$ test cases follow.
The only line of the test case contains two integers $n$ and $s$ ($1 \le n \le 10^{18}$; $1 \le s \le 162$).
Output
For each test case, print the answer: the minimum number of moves you need to perform in order to make the sum of digits of $n$ be less than or equal to $s$.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分