#include <iostream>
#include <unordered_map>
#include <vector>
#include <algorithm>
using namespace std;
 
int main() {
    int t;
    cin >> t; // Number of test cases
 
    while (t--) {
        int n, k;
        cin >> n >> k; // Number of cards and exchange rate
 
        vector<int> cards(n);
        unordered_map<int, int> frequency; // To store frequency of each number
 
        // Taking input for numbers on the cards and counting frequency
        for (int i = 0; i < n; ++i) {
            cin >> cards[i];
            frequency[cards[i]]++;
        }
 
        int removed_cards = 0;
 
        // Iterate over each frequency to determine cards removed by exchanges
        for (auto& pair : frequency) {
            // Calculate how many full sets of k cards can be made for this number
            int full_sets = pair.second / k;
            // Update total removed cards
            removed_cards += full_sets * k;
        }
 
        // Calculate the remaining cards after all possible exchanges
        int remaining_cards = n - removed_cards;
 
        // Check for cards with counts less than k
        for (auto& pair : frequency) {
            if (pair.second < k && pair.second > 0) {
                remaining_cards += pair.second;
                break;
            }
        }
 
        cout << remaining_cards << endl;
    }
 
    return 0;
}
 

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7
5 3
4 1 1 4 4
1 10
7
7 2
4 2 1 100 5 2 3
10 4
1 1 1 1 1 1 1 1 1 1
5 2
3 8 1 48 7
6 2
10 20 30 10 20 40
6 3
10 20 30 10 20 40