#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#define REP(i,n) for(int i=0;i<(n);++i)
#define SORT(a) sort((a).begin(),(a).end())
#define PB push_back
using namespace std;
typedef vector<int> VI;
typedef queue<int> QI;

int main(){
  int N, K;
  cin >> N >> K;
  VI v;
  REP(i,N){
    int n;
    cin >> n;
    v.PB(n);
  }
  SORT(v);
  cout << v[N-1] - v[0] << endl;
}