#include <iostream>

using namespace std;

int main(){
  int N, K, x;
  int nmax, nmin;
  cin >> N >> K;
  for(int i=0; i<N; i++){
    cin >> x;
    if(i != 0){
      if(nmax < x) nmax = x;
      if(nmin > x) nmin = x;
    }
    else{
      nmax = x;
      nmin = x;
    }
  }
  cout << nmax - nmin << endl;
}