use std::io::Write;
use std::collections::*;

type Map<K, V> = BTreeMap<K, V>;
type Set<T> = BTreeSet<T>;
type Deque<T> = VecDeque<T>;

fn run() {
    input! {
        n: i64,
        m: usize,
        a: i64,
        b: i64,
        c: [i64; m],
    }
    let mut c = c;
    c.sort();
    let mut divisor = vec![];
    for i in (1..).take_while(|i| i * i <= n) {
        if n % i == 0 {
            for &d in [i, n / i].iter() {
                divisor.push((d, c.binary_search(&d).is_err()));
            }
        }
    }
    divisor.extend(c.iter().map(|c| (*c, false)));
    divisor.sort();
    divisor.dedup();
    let inf = std::i64::MAX / 2;
    let mut dp = vec![inf; divisor.len()];
    dp[0] = 0;
    for i in 0..divisor.len() {
        let (d, ok) = divisor[i];
        if !ok || d == inf {
            continue;
        }
        let v = dp[i];
        for j in (i + 1)..divisor.len() {
            if divisor[j].0 % d == 0 {
                if !divisor[j].1 {
                    break;
                }
                dp[j] = dp[j].min(v + (divisor[j].0 / d - 1) * a + b);
            }
        }
    }
    let mut ans = dp[divisor.len() - 1];
    if ans >= inf {
        ans = b - 1;
    }
    ans -= b;
    println!("{}", ans);
}

fn main() {
    run();
}

// ---------- begin input macro ----------
// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
#[macro_export]
macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

#[macro_export]
macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};
    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

#[macro_export]
macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };
    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };
    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };
    ($iter:expr, bytes) => {
        read_value!($iter, String).bytes().collect::<Vec<u8>>()
    };
    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };
    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}
// ---------- end input macro ----------