#include <algorithm>
#include <iostream>

using namespace std;

int main(int argc, const char* argv[])
{
	int N, K;
	cin >> N >> K;
	int Ns[N];
	for (auto&& n : Ns) cin >> n;
	sort(Ns, &Ns[N]);
	cout << Ns[N - 1] - Ns[0] << endl;
	return 0;
}