fn main() {
    let p1: u32 = input_line()[0];
    let p2: u32 = input_line()[0];
    let n: usize = input_line()[0];

    let mut rv: Vec<u32> = Vec::new();
    for _i in 0..n {
        rv.push(input_line::<u32>()[0]);
    }

    rv.sort();
    let mut cost = 0;
    for i in 1..n {
        if rv[i] == rv[i - 1] {
            cost += p1 + p2;
        }
    }
    println!("{}", cost);
}

fn input_line<T: std::str::FromStr>() -> Vec<T> {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}