#include <bits/stdc++.h>
using namespace std;

using ll = long long;

int main() {
    int t;
    cin >> t;

    while (t--) {
        int n, k;
        cin >> n >> k;

        vector<int> a(n);

        for (int i = 0; i < n; i++) {
            cin >> a[i];
        }

        int i = 0;
        ll ans = 0;
        ll prev = -1;

        while (i < n) {
            int j = i;

            // Find group of equal elements
            while (j < n && a[i] == a[j]) {
                j++;
            }

            // First value that this group can take
            ll st = max(prev + 1, (ll)a[i]);

            // Assign consecutive values
            for (int p = i; p < j; p++) {
                ll fin = st + (p - i);

                ans += fin - a[i];

                prev = fin;
            }

            i = j;
        }

        cout << ans << endl;
    }
}