fn read() -> (usize, Vec<i64>, Vec<i64>) {
    let mut s = String::new();
    use std::io::Read;
    std::io::stdin().read_to_string(&mut s).unwrap();
    let mut it = s.trim().split_whitespace();
    let mut next = || it.next().unwrap().parse::<i64>().unwrap();
    let k = next() as usize;
    let n = next() as usize;
    let a = (0..k).map(|_| next()).collect::<Vec<_>>();
    let b = (0..k).map(|_| next()).collect::<Vec<_>>();
    (n, a, b)
}

pub fn kitamasa<T, F, G>(a: &[T], b: &[T], mut n: usize, zero: T, one: T, add: F, mul: G) -> T
where
    T: Clone,
    F: Fn(&T, &T) -> T,
    G: Fn(&T, &T) -> T,
{
    assert!(a.len() == b.len() && a.len() > 0);
    let k = a.len();
    let calc = |x: &[T], y: &[T]| -> Vec<T> {
        let mut z = vec![zero.clone(); x.len() + y.len() - 1];
        for (i, x) in x.iter().enumerate() {
            for (z, y) in z[i..].iter_mut().zip(y.iter()) {
                *z = add(z, &mul(x, y));
            }
        }
        for i in (k..z.len()).rev() {
            let p = z.pop().unwrap();
            for (z, b) in z[(i - k)..].iter_mut().zip(b.iter()) {
                *z = add(z, &mul(&p, b));
            }
        }
        z
    };
    let mut t = vec![zero.clone()];
    let mut s = vec![zero.clone()];
    t[0] = one.clone();
    if k > 1 {
        s.push(one);
    } else {
        s[0] = b[0].clone();
    }
    while n > 0 {
        if n & 1 == 1 {
            t = calc(&t, &s);
        }
        s = calc(&s, &s);
        n >>= 1;
    }
    let mut ans = zero;
    for (t, a) in t.iter().zip(a.iter()) {
        ans = add(&ans, &mul(t, a));
    }
    ans
}

fn main() {
    let (n, a, b) = read();
    let inf = 10i64.pow(18) + 1;
    let ans = kitamasa(&a, &b, n, -inf, inf, |a, b| std::cmp::max(*a, *b), |a, b| std::cmp::min(*a, *b));
    println!("{}", ans);
}