D. Decrease the Sum of Digitstime limit per test2 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputYou 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.InputThe 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).OutputFor 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.ExampleInput
5
2 1
1 1
500 4
217871987498122 10
100000000000000001 1
Output
8
0
500
2128012501878
899999999999999999

5
2 1
1 1
500 4
217871987498122 10
100000000000000001 1

8 0 500 2128012501878 899999999999999999 
['greedy', 'math', '*1500']