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:
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Random;
import java.util.StringTokenizer;
import java.util.*;

public class PhoenixAndBeauty {
    static final int MAXN = 1000_006;
    static final long MOD = (long) 1e9 + 7;
	public static void main(String[] args) throws IOException {
		MyScanner s = new MyScanner();
		Print p = new Print();
		int t = s.nextInt();
		TreeSet<Integer> hset;
		while( t --> 0 ) {
			int n = s.nextInt();
			int k = s.nextInt();
			hset = new TreeSet<>();
			for( int i=0; i<n; i++ ) {
				hset.add(s.nextInt());
			}
			
			if( hset.size() > k ) {
				p.println(-1);
			}else {
				p.println(n*k);
				for( int i=0; i<n; i++ ) {
					for( int an: hset ) {
						p.print(an+" ");
					}
					for( int j=0; j<k - hset.size(); j++ ) {
						p.print("1 ");
					}
				}
				p.println("");
			}
		}
		p.close();
	}
	
	public static class Pair implements Comparable<Pair> {
		int first;
		int second;
		
		public Pair( int a, int b ) {
			this.first = a;
			this.second = b;
		}

		@Override
		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
			return o.first - first;
		}
		
		
	}
	
	public static class Helper {
	    long MOD = (long) 1e9 + 7;
	    int MAXN = 1000_006;;
	    Random rnd;
	 
	    public Helper(long mod, int maxn) {
	        MOD = mod;
	        MAXN = maxn;
	        rnd = new Random();
	    }
	    
	    public Helper() {
	    	
	    }
	    
	    public static int[] sieve;
	    public static ArrayList<Integer> primes;
	 
	    public void setSieve() {
	        primes = new ArrayList<>();
	        sieve = new int[MAXN];
	        int i, j;
	        for (i = 2; i < MAXN; ++i)
	            if (sieve[i] == 0) {
	                primes.add(i);
	                for (j = i; j < MAXN; j += i) {
	                    sieve[j] = i;
	                }
	            }
	    }
	 
	 
	    public static long[] factorial;
	 
	    public void setFactorial() {
	        factorial = new long[MAXN];
	        factorial[0] = 1;
	        for (int i = 1; i < MAXN; ++i) factorial[i] = factorial[i - 1] * i % MOD;
	    }
	 
	    public long getFactorial(int n) {
	        if (factorial == null) setFactorial();
	        return factorial[n];
	    }
	 
	    public long ncr(int n, int r) {
	        if (r > n) return 0;
	        if (factorial == null) setFactorial();
	        long numerator = factorial[n];
	        long denominator = factorial[r] * factorial[n - r] % MOD;
	        return numerator * pow(denominator, MOD - 2, MOD) % MOD;
	    }
	 
	 
	    public long[] getLongArray(int size, MyScanner s) throws Exception {
	        long[] ar = new long[size];
	        for (int i = 0; i < size; ++i) ar[i] = s.nextLong();
	        return ar;
	    }
	 
	    public int[] getIntArray(int size, MyScanner s) throws Exception {
	        int[] ar = new int[size];
	        for (int i = 0; i < size; ++i) ar[i] = s.nextInt();
	        return ar;
		}
	 
	    public int[] getIntArray(String s)throws Exception
	    {
	        s = s.trim().replaceAll("\\s+", " ");
	        String[] strs = s.split(" ");
	        int[] arr = new int[strs.length];
	        for(int i = 0; i < strs.length; i++)
	        {
	            arr[i] =  Integer.parseInt(strs[i]);
	        }
	        return arr;
	    }
	 
		public long gcd(long a, long b) {
	        return b == 0 ? a : gcd(b, a % b);
	    }
	 
	    public int gcd(int a, int b) {
	        return b == 0 ? a : gcd(b, a % b);
	    }
	 
	 
	    public long max(long[] ar) {
	        long ret = ar[0];
	        for (long itr : ar) ret = Math.max(ret, itr);
	        return ret;
	    }
	 
	    public int max(int[] ar) {
	        int ret = ar[0];
	        for (int itr : ar) ret = Math.max(ret, itr);
	        return ret;
	    }
	 
	    public long min(long[] ar) {
	        long ret = ar[0];
	        for (long itr : ar) ret = Math.min(ret, itr);
	        return ret;
	    }
	 
	    public int min(int[] ar) {
	        int ret = ar[0];
	        for (int itr : ar) ret = Math.min(ret, itr);
	        return ret;
	    }
	 
	 
	    public long sum(long[] ar) {
	        long sum = 0;
	        for (long itr : ar) sum += itr;
	        return sum;
	    }
	 
	    public long sum(int[] ar) {
	        long sum = 0;
	        for (int itr : ar) sum += itr;
	        return sum;
	    }
	 

	 
	    public long pow(long base, long exp, long MOD) {
	        base %= MOD;
	        long ret = 1;
	        while (exp > 0) {
	            if ((exp & 1) == 1) ret = ret * base % MOD;
	            base = base * base % MOD;
	            exp >>= 1;
	        }
	        return ret;
	    }
	 

	}

	
    static class Print {
        private BufferedWriter bw;
 
        public Print() {
            this.bw = new BufferedWriter(new OutputStreamWriter(System.out));
        }
        public void print(Object object) throws IOException {
            bw.append("" + object);
        }
        public void println(Object object) throws IOException {
            print(object);
            bw.append("\n");
        }
        public void close() throws IOException {
            bw.close();
        }
    }
	
	
	
	
	
	
    public static class MyScanner {
	      BufferedReader br;
	      StringTokenizer st;
	 
	      public MyScanner() {
	         br = new BufferedReader(new InputStreamReader(System.in));
	      }
	 
	      String next() {
	          while (st == null || !st.hasMoreElements()) {
	              try {
	                  st = new StringTokenizer(br.readLine());
	              } catch (IOException e) {
	                  e.printStackTrace();
	              }
	          }
	          return st.nextToken();
	      }
	 
	      int nextInt() {
	          return Integer.parseInt(next());
	      }
	 
	      long nextLong() {
	          return Long.parseLong(next());
	      }
	 
	      double nextDouble() {
	          return Double.parseDouble(next());
	      }
	 
	      String nextLine(){
	          String str = "";
		  try {
		     str = br.readLine();
		  } catch (IOException e) {
		     e.printStackTrace();
		  }
		  return str;
	      }
	}


}