#include <iostream>

#define MAX_N 9
#define INF 1000000000

using namespace std;

int N, K;

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