#include <iostream>
#include <fstream>
using namespace std;

int main (void) {
	fstream fs;
	fs.open("seat.in", fstream::in);
	int k;
	fs >> k;

	bool machines[1000]={0};
	for (int i=0; i<k; i++) {
		int p,m;
		fs >> p >> m;
		int answer = 0;
		for (int z = 0; z<501; z++ ) {
			machines[z]=false;
		}
		for (int j=0; j<p; j++) {
			int tmp;
			fs >> tmp;
			if (tmp < 501) {
			
			if (machines[tmp]==true) {
				answer++;
			}
			else {
			
			machines[tmp] = true;
			}
			}
		}
		cout << "Data Set " << i+1 << ":\n" << answer << endl << endl;


	}
}