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
/*And I thought my jokes were bad*/
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define dbg puts("Viva la vida");
#define CHECK(x) cout << (#x) << " is " << (x) << endl;
#define nl puts("");
#define mp make_pair
#define IN(x) scanf("%d",&x);
#define INL(x) scanf("%lld",&x);
#define OUT(x) printf("%d",x);
#define OUTL(x) printf("%lld",x);
#define MAX 200005
#define MOD 1000000009
#define INF (1 << 31)
#define CASE(x,y) printf("Case %d: %d\n",++x,y);
#define FASTIO ios::sync_with_stdio(false);cin.tie(0);
#define PI acos(-1.0)
#define EPS 1e-19
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// #define int ll
/*
	When I get older
	I will be stronger
	they'll call me freedom
	just like a waving flag
*/
int arr[MAX],n;
int dp[505][505][505];
int sol(int i,int mx,int x)
{
	if(i==n)
		return 0;

	if(arr[i]<mx)
	{
		return 505;
	}
	int &ret=dp[i][mx][x];
	if(~ret) return ret;
	if(arr[i]<=x||x<mx)
		return ret=sol(i+1,arr[i],x);
	else
		return ret=min(sol(i+1,arr[i],x),1+sol(i+1,x,arr[i]));
}


void solve()
{
	int i,j,k,l,r,m,a,b,c,d,x,y,z,t,p;
	cin>>n>>x;
	for(i=0;i<n;i++)
		cin>>arr[i];
	for(i=0;i<=n;i++)
		for(j=0;j<=500;j++)
			for(k=0;k<=500;k++)
				dp[i][j][k]=-1;
	int ans=sol(0,0,x);
	if(ans>=505)
		ans=-1;
	cout<<ans<<endl;


}
int32_t main()
{
	FASTIO
    int t=1;
    cin>>t;
    while(t--) solve();
    return 0;
}