#include <bits/stdc++.h>
using namespace std;

template<typename T>
void fin(T a){
  cout<<a<<endl;
  exit(0);
}

signed main(){
    int n,k;cin>>n>>k;
    set<int> s;
    while(n--){int a;cin>>a;s.insert(a);}
    cout<<*s.rbegin()-*s.begin()<<endl;
}