Decrease the Sum of Digits
题意翻译
给定一个数 $n$,将 $n$ 加上一个数 $k$,使得和的**数码**和不大于 $s$,求 $k$ 的最小值。
输入包含多组数据。
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.
输入输出格式
输入格式
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 $ ).
输出格式
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 $ .
输入输出样例
输入样例 #1
5
2 1
1 1
500 4
217871987498122 10
100000000000000001 1
输出样例 #1
8
0
500
2128012501878
899999999999999999