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.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class problemD {
    static class Solution {
        void solve() {
            int n = fs.nextInt(), x = fs.nextInt();
            int[] a = fs.readArray(n);

            int ans = 0;
            while (ans <= n+1) {
                if (isSorted(a, n)) {
                    out.println(ans);
                    return;
                }
                x = makeSwap(a, n, x);
                if (x == -1) {
                    out.println(-1);
                    return;
                }
                ans++;
            }
            out.println(-1);
        }

        int makeSwap(int[] a, int n, int x) {
            for (int i = 0 ; i < n ; i ++ ) {
                if (a[i] > x) {
                    int ret = a[i];
                    a[i] = x;
                    return ret;
                }
            }
            return -1;
        }

        boolean isSorted(int[] a, int n) {
            for (int i = 1; i < n ; i ++ ) {
                if (a[i] < a[i-1]) return false;
            }
            return true;
        }
    }

    public static void main(String[] args) throws Exception {
        int T = 1;
        T = fs.nextInt();
        Solution solution = new Solution();
        for (int t = 0; t < T; t++) solution.solve();
        out.close();
    }

    static void debug(Object... O) {
        System.err.println("DEBUG: " + Arrays.deepToString(O));
    }

    private static FastScanner fs = new FastScanner();
    private static PrintWriter out = new PrintWriter(System.out);

    static class FastScanner { // Thanks SecondThread.
        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) {
                    e.printStackTrace();
                }
            return st.nextToken();
        }

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

        int[] readArray(int n) {
            int[] a = new int[n];
            for (int i = 0; i < n; i++) a[i] = nextInt();
            return a;
        }

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

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

        String nextString() {
            return next();
        }
    }
}
