#include <stdio.h>
#include <stdlib.h>
int main()
{
  int N, K, i;
  int *n;
  scanf("%d", &N);
  scanf("%d", &K);
  n = (int*)malloc(sizeof(int)*N);
  for (i=0; i<N; i++) scanf("%d", n+i);

  int min = n[0];
  int max = n[0];
  for (i=1; i<N; i++) {
    if (n[i] < min) {
      min = n[i];
      continue;
    }
    if (max < n[i]) {
      max = n[i];
      continue;
    }
  }
  printf("%d\n", max-min);
  return 0;
}