#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; ++i)
typedef long long ll;
using namespace std;

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

    int N, K;
    cin >> N >> K;
    vector<ll> A(N);
    rep(i, N) cin >> A[i];
    sort(A.begin(), A.end());

    ll ans = 0;
    do {
        ll cur = K;
        rep(i, N) cur %= A[i];
        ans = max(ans, cur);
    } while (next_permutation(A.begin(), A.end()));
    cout << ans << "\n";

    return 0;
}