#D5390. Zero Remainder Array
Zero Remainder Array
Zero Remainder Array
You are given an array a consisting of n positive integers.
Initially, you have an integer x = 0. During one move, you can do one of the following two operations:
- Choose exactly one i from 1 to n and increase a_i by x (a_i := a_i + x), then increase x by 1 (x := x + 1).
- Just increase x by 1 (x := x + 1).
The first operation can be applied no more than once to each i from 1 to n.
Your task is to find the minimum number of moves required to obtain such an array that each its element is divisible by k (the value k is given).
You have to answer t independent test cases.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 10^9) — the length of a and the required divisior. The second line of the test case contains n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ 10^9), where a_i is the i-th element of a.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain such an array that each its element is divisible by k.
Example
Input
5 4 3 1 2 1 3 10 6 8 7 1 8 3 7 5 10 8 9 5 10 20 100 50 20 100500 10 25 24 24 24 24 24 24 24 24 24 24 8 8 1 2 3 4 5 6 7 8
Output
6 18 0 227 8
Note
Consider the first test case of the example:
- x=0, a = [1, 2, 1, 3]. Just increase x;
- x=1, a = [1, 2, 1, 3]. Add x to the second element and increase x;
- x=2, a = [1, 3, 1, 3]. Add x to the third element and increase x;
- x=3, a = [1, 3, 3, 3]. Add x to the fourth element and increase x;
- x=4, a = [1, 3, 3, 6]. Just increase x;
- x=5, a = [1, 3, 3, 6]. Add x to the first element and increase x;
- x=6, a = [6, 3, 3, 6]. We obtained the required array.
Note that you can't add x to the same element more than once.
inputFormat
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains two integers n and k (1 ≤ n ≤ 2 ⋅ 10^5; 1 ≤ k ≤ 10^9) — the length of a and the required divisior. The second line of the test case contains n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ 10^9), where a_i is the i-th element of a.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
outputFormat
Output
For each test case, print the answer — the minimum number of moves required to obtain such an array that each its element is divisible by k.
Example
Input
5 4 3 1 2 1 3 10 6 8 7 1 8 3 7 5 10 8 9 5 10 20 100 50 20 100500 10 25 24 24 24 24 24 24 24 24 24 24 8 8 1 2 3 4 5 6 7 8
Output
6 18 0 227 8
Note
Consider the first test case of the example:
- x=0, a = [1, 2, 1, 3]. Just increase x;
- x=1, a = [1, 2, 1, 3]. Add x to the second element and increase x;
- x=2, a = [1, 3, 1, 3]. Add x to the third element and increase x;
- x=3, a = [1, 3, 3, 3]. Add x to the fourth element and increase x;
- x=4, a = [1, 3, 3, 6]. Just increase x;
- x=5, a = [1, 3, 3, 6]. Add x to the first element and increase x;
- x=6, a = [6, 3, 3, 6]. We obtained the required array.
Note that you can't add x to the same element more than once.
样例
5
4 3
1 2 1 3
10 6
8 7 1 8 3 7 5 10 8 9
5 10
20 100 50 20 100500
10 25
24 24 24 24 24 24 24 24 24 24
8 8
1 2 3 4 5 6 7 8
6
18
0
227
8
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