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();
    let amin = a[0];
    a.reverse();
    a.pop();
    let mut result = 0usize;
    let n = a.len();
    for i in 0..1<<n {
        let temp = (0..n).filter(|&j| ((i >> j) & 1) == 1).map(|j| a[j]).fold(k, |base, modval| base % modval);
        result = result.max(temp % amin);
    }
    println!("{}", result);
}