#include <algorithm>
#include <iostream>

using namespace std;

int N, K, n;
int ma, mi;

int main() {
	cin >> N >> K;
	for (int i = 0; i < N; i++) {
		cin >> n;
		if (i == 0) {
			ma = mi = n;
		} else {
			mi = min(mi, n);
			ma = max(ma, n);
		}
	}
	cout << (ma - mi) << endl;
	return 0;
}