#include <stdio.h>
#include <stdlib.h>

int compare(const void *a,const void *b)
{
	return *(short *)a - *(short *)b;
}

int main(void)
{
	char n,k,i;
	short m[9];

	scanf("%hhd",&n);
	scanf("%hhd",&k);
	for (i=0;i<n;i++) scanf("%hd",&m[i]);

	qsort(m,n,sizeof(short),compare);

	printf("%hd\n",m[n-1]-m[0]);

	return 0;
}