/* -*- coding: utf-8 -*-
 *
 * 21.cc: No.21 平均の差 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int INF = 1 << 30;

/* typedef */

/* global variables */

/* subroutines */

/* main */

int main() {
  int n, k;
  cin >> n >> k;

  int mind = INF, maxd = 0;
  for (int i = 0; i < n; i++) {
    int ai;
    cin >> ai;
    if (mind > ai) mind = ai;
    if (maxd < ai) maxd = ai;
  }

  printf("%d\n", maxd - mind);
  return 0;
}