#include<stdio.h>
int main(void){
int i, min = 1000, max = 0;
int N, K;
int n[9];
scanf ("%d%d", &N, &K);
for ( i = 0; i < N; i++){
	scanf ("%d", &n[i]);
	if ( min > n[i])
		min = n[i];
	if ( max < n[i])
		max = n[i];
}
printf ("%d", max - min);
	return 0;
}