#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<climits>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
#include<tuple>
#include<unordered_set>
#include<unordered_map>
#include<random>
#include<array>
#include<cassert>
using namespace std;
#define INF ((1<<30)-1)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()



int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);

	int n, k;
	int a[20];
	cin >> n >> k;
	rep(i, n)cin >> a[i];

	sort(a, a + n, greater<int>());


	vector<int> dp[20];
	dp[0].push_back(k);

	rep(i, n) {
		for (int x : dp[i]) {
			for (int j = i + 1; j < n;j++) {
				dp[j].push_back(x % a[j]);
			}
		}
	}

	cout << *max_element(all(dp[n - 1])) << endl;


	
	return 0;
}