use std::collections::HashSet;

fn main() {
    let mut xx = String::new();
    std::io::Read::read_to_string(&mut std::io::stdin(), &mut xx).ok();
    let xx: Vec<usize> = xx.split_whitespace().flat_map(str::parse).collect();

    let n_duplicate = xx[2] - xx[3..].iter().collect::<HashSet<_>>().len();

    println!("{}", n_duplicate * (xx[0] + xx[1]));
}