#include <iostream>

using namespace std;

int main() {
    int n, k, max, min, tmp;

    cin >> n;
    cin >> k;
    cin >> max;
    min = max;
    for (int i = 1; i < n; i++) {
        cin >> tmp;
        if (tmp < min) {
            min = tmp;
        }
        if (tmp > max) {
            max = tmp;
        }
    }
    cout << max - min << endl;

    return 0;
}