#include <iostream>
using namespace std;

int main() {
  int N, K;
  int min = 1000;
  int max = 1;
  cin >> N >> K;
  for (int i = 0; i < N; i++) {
    int n;
    cin >> n;
    min = n < min ? n : min;
    max = n > max ? n : max;
  }
  cout << max - min << endl;
}