fn main() {
    let mut nk = String::new();
    std::io::stdin().read_line(&mut nk).ok();
    let nk: Vec<usize> = nk.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let n = nk[0];
    let k = nk[1];
    let mut a = String::new();
    std::io::stdin().read_line(&mut a).ok();
    let mut a: Vec<usize> = a.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();

    a.sort();
    a.reverse();
    let amins = a.pop().unwrap();
    let n = n-1;
    let mut result = k % amins;
    for i in 0..1<<n {
        let mut val = k;
        for j in 0..n {
            if ((i >> j) & 1) == 1 {
                val %= a[j];
            }
        }
        result = result.max(val % amins);
    }
    println!("{}", result);
}