Problem: Phoenix loves beautiful arrays. An array is beautiful if all its subarrays of length k have the same sum. A subarray of an array is any sequence of consecutive elements.

Phoenix currently has an array a of length n. He wants to insert some number of integers, possibly zero, into his array such that it becomes beautiful. The inserted integers must be between 1 and n inclusive. Integers may be inserted anywhere (even before the first or after the last element), and he is not trying to minimize the number of inserted integers.

Input

The input consists of multiple test cases. The first line contains an integer t (1 ≤ t ≤ 50) — the number of test cases.

The first line of each test case contains two integers n and k (1 ≤ k ≤ n ≤ 100).

The second line of each test case contains n space-separated integers (1 ≤ a_i ≤ n) — the array that Phoenix currently has. This array may or may not be already beautiful.

Output

For each test case, if it is impossible to create a beautiful array, print -1. Otherwise, print two lines.

The first line should contain the length of the beautiful array m (n ≤ m ≤ 10^4). You don't need to minimize m.

The second line should contain m space-separated integers (1 ≤ b_i ≤ n) — a beautiful array that Phoenix can obtain after inserting some, possibly zero, integers into his array a. You may print integers that weren't originally in array a.

If there are multiple solutions, print any. It's guaranteed that if we can make array a beautiful, we can always make it with resulting length no more than 10^4.

Example

Input


4
4 2
1 2 2 1
4 3
1 2 2 1
3 2
1 2 3
4 4
4 3 4 2


Output


5
1 2 1 2 1
4
1 2 2 1
-1
7
4 3 2 1 4 3 2

Note

In the first test case, we can make array a beautiful by inserting the integer 1 at index 3 (in between the two existing 2s). Now, all subarrays of length k=2 have the same sum 3. There exists many other possible solutions, for example: 

  * 2, 1, 2, 1, 2, 1 
  * 1, 2, 1, 2, 1, 2 



In the second test case, the array is already beautiful: all subarrays of length k=3 have the same sum 5.

In the third test case, it can be shown that we cannot insert numbers to make array a beautiful.

In the fourth test case, the array b shown is beautiful and all subarrays of length k=4 have the same sum 10. There exist other solutions also.

Solution (in JAVA):

Solution:
//LOGIC

/*For an array to be beautiful for some k, the array must be periodic with period k. 
If there exists more than k distinct numbers in the array a, there is no answer and we print -1 (because the array cannot be periodic with period k).
Otherwise, we propose the following construction.

Consider a list of all the distinct numbers in array a.
If there are less than k of them, we will append some 1s (or any other number) until the list has size k.
We can just print this list n times. The length of our array b is nk, which never exceeds 10^4.
Array b can always be constructed by inserting some numbers into array a because every number in a corresponds to one list.

Time complexity for each test case: O(nlogn+nk)*/

// for set defination- https://www.geeksforgeeks.org/set-in-java/
import java.io.*;
import java.util.*;
public class BeautifulArray {
    static  Scanner sc = new Scanner(System.in);
    public static void main(String[] args) {
    //static  Scanner sc = new Scanner(System.in);
		int t = sc.nextInt();
		while(t-->0) {
			solve();
        }
        sc.close();
        return;
    }
    public static void solve() {
		int n = sc.nextInt();
		int k = sc.nextInt();
		Set<Integer> set = new HashSet<Integer>();
		
		for(int i = 0;i < n;i++) {
			set.add(sc.nextInt());
		}
		
		if(set.size() > k) {
			System.out.println(-1);
			return;
		}
		
		System.out.println(k * n);
		for(int i = 0;i < n;i++) {
			for(Integer ix : set) {
				System.out.print(ix + " ");
			}
			
			for(int xxi = set.size();xxi < k;xxi++)System.out.print("1 ");
		}System.out.println();
    }
}