import java.io.*;
import java.util.stream.*;

// 処理
class Process {
    private PrintWriter printWriter;
    private int[] n;

    Process(PrintWriter printWriter, int[] n) {
        this.printWriter = printWriter;
        this.n = n;
    }

    // 結果を出力
    void printResult() throws IOException {
        printWriter.println(IntStream.of(n).max().getAsInt() - IntStream.of(n).min().getAsInt());
    }
}

public class Main {
    public static void main(String[] args) throws IOException {
        var bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        var printWriter    = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

        // 入力
        int N = Integer.parseInt(bufferedReader.readLine().trim());

        int K = Integer.parseInt(bufferedReader.readLine().trim());

        int[] n = new int[N];
        for(int i = 0; i < N; i++) {
            n[i] = Integer.parseInt(bufferedReader.readLine().trim());
        }

        // Process クラスで処理を行う
        var process = new Process(printWriter, n);
        process.printResult();

        // 各ストリームを閉じる
        // 出力ストリームを閉じるときに標準出力に文字を出力する
        bufferedReader.close();
        printWriter.close();
    }
}