/*
yukicoder No.21
作成者：ヒロソフ
使用言語：C++(new , delete使用の為）
*/
#include <stdio.h>
 
int main(void) {
	int N, K, *pNums ;
	scanf("%d", &N);
	scanf("%d", &K);
	pNums = new int[N];
	for (int i = 0; i < N; i++) {
		scanf("%d", pNums + i);
	}
	int Min = *(pNums), Max = *(pNums)  ,Current;
	for (int i = 1; i < N; i++) {
		Current = *(pNums + i);
		Min = (Current < Min) ? Current : Min;
		Max = (Current > Max) ? Current : Max;
	}
	printf("%d\n", Max - Min);
	delete[]pNums;
	return 0;
}