// No.21 平均の差
// https://yukicoder.me/problems/no/21
//

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int solve(vector<int> &numbers);


int main() {
    int N, K;
    cin >> N >> K;
    vector<int> numbers(N);
    for (auto i = 0; i < N; i++)
        cin >> numbers[i];

    int ans = solve(numbers);
    cout << ans << endl;
}

int solve(vector<int> &numbers) {
    sort(numbers.begin(), numbers.end());
    return numbers[numbers.size()-1] - numbers[0];
}