#include<bits/stdc++.h>
using namespace std;
long vitri(long n, long k, long a[])
{
	long dau = 0;
	long cuoi = n-1;
	while (dau < cuoi)
	{
		long giua = (dau +cuoi) / 2;
		if (k == a[giua]) return giua;
		if (k< a[giua]) cuoi = giua -1;
		else 
		if (k>a[giua]) dau = giua +1;
		}
	return -1;
}
int main()
{
	int t;
	cin >> t;
	while (t--)
	{
		long n, k;
		cin >> n >> k;
		long a[n];
		for  (int i = 1; i<=n ;i++)
		{
			cin >> a[i];
		}
		long u = vitri(n,k,a);
		if (u >= 0) cout << u;
		else cout << "NO";
		cout << endl;
	}
	return 0;
}

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1 2 3 4 5
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0 1 2 3 9 10