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
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.StringTokenizer;

/**
 *
 * @author is2ac
 */
public class D_99 {

    public static void main(String[] args) {
        FastScanner34 fs = new FastScanner34();
        StringBuilder sb = new StringBuilder();
   
        int t = fs.ni();
        for (int tc = 0; tc < t; tc++) {
            int n = fs.ni();
            int x = fs.ni();
            int[] a = fs.intArray(n);
            int[] b = new int[a.length+1];
            for (int i = 0; i < a.length; i++) {
                b[i] = a[i];
            }
            b[b.length-1] = x;
            Arrays.sort(b);
            int res = (int)(1e9);
            int p = -1;
            for (int i = 0; i < b.length; i++) {
                if (b[i]==x) p = i;
            }
            for (int i = 0; i < b.length; i++) {
                if (i>=p) res = Math.min(res,find(a,b,i));
            }
            if (res>=(int)(1e9)) res = -1;
            sb.append(res);
            sb.append("\n");
        }
        System.out.println(sb.toString());
    }
    public static int find(int[] a, int[] b, int ind) {
        int ct = 0, prev = -1, p = 0;
        for (int i = 0; i < b.length; i++) {
            if (i==ind) {
                continue;
            }
            if (b[i]!=a[p]) {
                if (prev != -1 && prev>a[p]) {
                    return (int)(1e9);
                }
                prev = a[p];
                ct++;
            }
            p++;
        }
        return ct;
    }
}

class FastScanner34 {

    BufferedReader br;
    StringTokenizer st;

    public FastScanner34() {
        br = new BufferedReader(new InputStreamReader(System.in), 32768);
        st = null;
    }

    String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int ni() {
        return Integer.parseInt(next());
    }

    int[] intArray(int N) {
        int[] ret = new int[N];
        for (int i = 0; i < N; i++) {
            ret[i] = ni();
        }
        return ret;
    }

    long nl() {
        return Long.parseLong(next());
    }

    long[] longArray(int N) {
        long[] ret = new long[N];
        for (int i = 0; i < N; i++) {
            ret[i] = nl();
        }
        return ret;
    }

    double nd() {
        return Double.parseDouble(next());
    }

    String nextLine() {
        String str = "";
        try {
            str = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return str;
    }
}


