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.*;
    import java.util.*;
    public class Main {
        final static long mod = 1000000007;
        static void debug(Object... args) {
            System.out.println(Arrays.deepToString(args));}
        static boolean isSorted(int [] ar)
        {
            for(int i=1;i<ar.length;i++)
            {
                if(ar[i-1]>ar[i])
                    return false;
            }
            return true;
        }
        public static void main(String[] args) throws Exception {
            InputReader sc = new InputReader(System.in);
            PrintWriter pw = new PrintWriter(System.out);
            Random gen = new Random();
            int test = sc.nextInt();
        o:    while (test-- > 0) {
                StringBuilder sb = new StringBuilder();
                int n = sc.nextInt();
                int x = sc.nextInt();
                int [] ar = sc.nextIntArray(n);
                if(isSorted(ar)) {
                    pw.println(0);
                    continue;
                }
                int steps = 0;
                for(int i=0;i<n;i++)
                {
                    if(ar[i]>x)
                    {
                        steps++;
                        int temp = ar[i];
                        ar[i] = x;
                        x = temp;

                        if(isSorted(ar))
                        {
                            pw.println(steps);
                            continue o;
                        }
                    }
                }
                pw.println(-1);
            }
            pw.flush();
            pw.close();
        }



        static class Data implements Comparable<Data> {
            int x;
            int y;

            public Data(int m, int n) {
                x = m;
                y = n;

            }

            @Override
            public int compareTo(Data o) {

                return o.y-y;
            }
        }


        static class InputReader {

            private final InputStream stream;
            private final byte[] buf = new byte[8192];
            private int curChar, snumChars;

            public InputReader(InputStream st) {
                this.stream = st;
            }

            public int read() {
                if (snumChars == -1)
                    throw new InputMismatchException();
                if (curChar >= snumChars) {
                    curChar = 0;
                    try {
                        snumChars = stream.read(buf);
                    } catch (IOException e) {
                        throw new InputMismatchException();
                    }
                    if (snumChars <= 0)
                        return -1;
                }
                return buf[curChar++];
            }

            public int nextInt() {
                int c = read();
                while (isSpaceChar(c)) {
                    c = read();
                }
                int sgn = 1;
                if (c == '-') {
                    sgn = -1;
                    c = read();
                }
                int res = 0;
                do {
                    res *= 10;
                    res += c - '0';
                    c = read();
                } while (!isSpaceChar(c));
                return res * sgn;
            }

            public long nextLong() {
                int c = read();
                while (isSpaceChar(c)) {
                    c = read();
                }
                int sgn = 1;
                if (c == '-') {
                    sgn = -1;
                    c = read();
                }
                long res = 0;
                do {
                    res *= 10;
                    res += c - '0';
                    c = read();
                } while (!isSpaceChar(c));
                return res * sgn;
            }

            public int[] nextIntArray(int n) {
                int [] a = new int[n];
                for (int i = 0; i < n; i++) {
                    a[i] = nextInt();
                }
                return a;
            }
            public long[] nextLongArray(int n) {
                long [] a = new long[n];
                for (int i = 0; i < n; i++) {
                    a[i] = nextLong();
                }
                return a;
            }

            public static int[] shuffle(int[] a, Random gen)
            { for(int i = 0, n = a.length;i < n;i++)
            { int ind = gen.nextInt(n-i)+i;
                int d = a[i];
                a[i] = a[ind];
                a[ind] = d;

            }
                return a;
            }
            public static long[] shuffle(long[] a, Random gen)
            { for(int i = 0, n = a.length;i < n;i++)
            { int ind = gen.nextInt(n-i)+i;
                long d = a[i];
                a[i] = a[ind];
                a[ind] = d;

            }
                return a;
            }


            public String readString() {
                int c = read();
                while (isSpaceChar(c)) {
                    c = read();
                }
                StringBuilder res = new StringBuilder();
                do {
                    res.appendCodePoint(c);
                    c = read();
                } while (!isSpaceChar(c));
                return res.toString();
            }

            public String nextLine() {
                int c = read();
                while (isSpaceChar(c))
                    c = read();
                StringBuilder res = new StringBuilder();
                do {
                    res.appendCodePoint(c);
                    c = read();
                } while (!isEndOfLine(c));
                return res.toString();
            }

            public boolean isSpaceChar(int c) {
                return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
            }

            private boolean isEndOfLine(int c) {
                return c == '\n' || c == '\r' || c == -1;
            }

        }

    }