You are given a sequence a consisting of n integers a_1, a_2, ..., a_n, and an integer x. Your task is to make the sequence a sorted (it is considered sorted if the condition a_1 ≤ a_2 ≤ a_3 ≤ ... ≤ a_n holds).

To make the sequence sorted, you may perform the following operation any number of times you want (possibly zero): choose an integer i such that 1 ≤ i ≤ n and a_i > x, and swap the values of a_i and x.

For example, if a = [0, 2, 3, 5, 4], x = 1, the following sequence of operations is possible:

  1. choose i = 2 (it is possible since a_2 > x), then a = [0, 1, 3, 5, 4], x = 2; 
  2. choose i = 3 (it is possible since a_3 > x), then a = [0, 1, 2, 5, 4], x = 3; 
  3. choose i = 4 (it is possible since a_4 > x), then a = [0, 1, 2, 3, 4], x = 5. 



Calculate the minimum number of operations you have to perform so that a becomes sorted, or report that it is impossible.

Input

The first line contains one integer t (1 ≤ t ≤ 500) — the number of test cases.

Each test case consists of two lines. The first line contains two integers n and x (1 ≤ n ≤ 500, 0 ≤ x ≤ 500) — the number of elements in the sequence and the initial value of x.

The second line contains n integers a_1, a_2, ..., a_n (0 ≤ a_i ≤ 500).

The sum of values of n over all test cases in the input does not exceed 500.

Output

For each test case, print one integer — the minimum number of operations you have to perform to make a sorted, or -1, if it is impossible.

Example

Input


6
4 1
2 3 5 4
5 6
1 1 3 4 4
1 10
2
2 10
11 9
2 10
12 11
5 18
81 324 218 413 324


Output


3
0
0
-1
1
3
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Collections;
import java.util.StringTokenizer;


public class A {

    static class FastScanner {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st=new StringTokenizer("");
        String next() {
            while (!st.hasMoreTokens())
                try {
                    st=new StringTokenizer(br.readLine());
                } catch (IOException e) {}
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }
        long nextLong() {
            return Long.parseLong(next());
        }
    }

    static FastScanner fs = new FastScanner();

    public static boolean sorted(int[] arr)
    {
        if(arr.length == 1)
            return true;
        for(int i = 1; i < arr.length; ++i)
        {
            if(arr[i] < arr[i - 1])
                return false;
        }
        return true;
    }

    public static void solve() {
        int n, x;
        n = fs.nextInt();
        x = fs.nextInt();
        int[] arr = new int[n];
        for(int i = 0; i < n; ++i)
            arr[i] = fs.nextInt();
        int ans = 0;
        int t;
        for(int i = 0; i < n; ++i)
        {
            if(sorted(arr) == true)
            {
                System.out.println(ans);
                return;
            }
            if(arr[i] > x)
            {
                t = arr[i];
                arr[i] = x;
                x = t;
                ans++;
            }
        }
        if(sorted(arr) == true)
        {
            System.out.println(ans);
            return;
        }
        System.out.println(-1);
    }

    public static void main(String[] args)
    {
        int t = 1;
        t = fs.nextInt();
        while(t-- > 0)
        {
            solve();
        }
    }
}