#include <bits/stdc++.h>
using namespace std;
 
void solve()
{
    int n, k;
    cin >> n >> k;
 
    int val = 1, cnt = 0;
 
    for(int i = 0; i < n; i++)
    {
        int x;
        cin >> x;
 
        if(x == val)
        {
            val ++;
            cnt ++;
        }
    }
 
    int rem = n - cnt;
    int ans = rem/k;
 
    if(rem % k != 0)
        ans ++;
 
    cout << ans << endl;
}
 
int main() {
    // your code goes here
    int t;
    cin >> t;
 
    while(t--)
        solve();
}

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

NAozIDIKMSAyIDMKMyAxCjMgMSAyCjQgMgoxIDMgMiA0CjQgMgoyIDMgMSA0Cg==

4
3 2
1 2 3
3 1
3 1 2
4 2
1 3 2 4
4 2
2 3 1 4