#include <iostream>
using namespace std;

int main()
{
	int N, K;
	while( cin >> N ){
		cin >> K;
		int ma = 0, mi = 1001;
		for( int i = 0; i < N; ++i ){
			int m;
			cin >> m;
			if( m > ma ) ma = m;
			if( m < mi ) mi = m;
		}
		cout << ma - mi << endl;
	}

	return 0;
}