#include <iostream>
#include <algorithm>
#include <vector>

void solve() {
    int n, k;
    std::cin >> n >> k;

    std::vector<int> xs(n);
    for (auto& x : xs) std::cin >> x;

    std::sort(xs.rbegin(), xs.rend());
    int xmin = xs.back();
    xs.pop_back();
    --n;

    int ans = 0;
    for (int b = 0; b < (1 << n); ++b) {
        int r = k;
        for (int i = 0; i < n; ++i) {
            if ((b >> i) & 1) r %= xs[i];
        }
        r %= xmin;
        ans = std::max(ans, r);
    }

    std::cout << ans << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}