#include <iostream>
#include <cmath>

using namespace std;

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

	int *obzartuchy = new int[proby];
	float *w_pudelku = new float[proby];
	float *suma = new float[proby];

	for (int i = 0; i < proby; i++)
	{
		cin >> obzartuchy[i];
		cin >> w_pudelku[i];
		float *czasy = new float[obzartuchy[i]];
		for (int j = 0; j < obzartuchy[i]; j++)
		{
			cin >> czasy[j];
			suma[i] += floor(86400.0 / czasy[j]);

		}
	}
	for (int i = 0; i<proby; i++)
	{
		int liczba = ceil(suma[i] / w_pudelku[i]);
		cout << liczba << endl;
	}
	system("pause");
	return 0;
}