#include <algorithm>
#include <vector>
#include <iostream>
using namespace std;

int solve(vector<int>& a, int k, int i=0) {
    while (i < a.size() && a[i] > k) i++;
    if (i == a.size()) return k;
    if (i == a.size() - 1) return k % a[i];
    return max(solve(a, k % a[i], i+1), solve(a, k, i+1));
}

int main() {
    int n, k; cin >> n >> k;
    vector<int> a(n); for (int i = 0; i < n; i++) cin >> a[i];
    sort(a.begin(), a.end(), greater<int>());
    cout << solve(a, k) << endl;
}