import std.stdio;

void main(){
	auto cin = new Cin();
	
	auto N = cin.line()[0];
	auto K = cin.line()[0];
	auto n = cin.line(N);
	
	n.sort();
	
	(n[$-1]-n[0]).writeln();
	//possible.writeln();
}
auto solve(){
}
unittest{
	
}


import std.stdio,std.conv,std.string;
import std.algorithm,std.array;

class Cin
{
	T[] line( T = size_t , string token = " " )( size_t m = 1 ){
		T[] arr = [];
		foreach( i ; 0..m ){
			arr ~= this.read!T();
		}
		return arr;
	}
	T[][] rect( T = size_t , string token = " " )( size_t m = 1 ){
		T[][] arr = new T[][](m);
		foreach( i ; 0..m ){
			arr[i] = this.read!T(token);
		}
		return arr;
	}
	private T[] read( T = size_t )( string token = " " ){
		T[] arr;
		foreach( elm ; readln().chomp().split(token) ){
			arr ~= elm.to!T();
		}
		return arr;
	}
}