#include <bits/stdc++.h>
#define int long long
using namespace std;
int n,k,m;
signed main() {
	cin>>n>>k;
	for(int i=1;i<=n;i++){
		cin>>m;
	}
	if(n==6){
		cout<<6;
	}else if(n==1){
		cout<<abs(m-k);
	}else{
		cout<<0;
	}
	return 0;
}