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

int main(void){
  int n,k,t;
  vector<int> v;
  
  cin >> n >> k;
  for (int i=0; i<n; i++){
    cin >> t;
    v.push_back(t);
  }
  sort(v.begin(), v.end());
  cout << (v[n-1]-v[0]) << endl;
  return 0;
}