use proconio::{input, marker::Usize1};

fn main() {
    input! {
        n:usize,
        m:usize,
        x:usize,
        mut ab:[(usize,Usize1);n],
        k:usize,
        c:[usize;k],
    }

    ab.sort_by(|x, y| y.0.cmp(&x.0));

    let mut seq = vec![];
    let mut i = 0;
    let mut j = 0;
    let mut used = vec![false; m];
    let mut fin = vec![false; n];
    let mut scores = vec![0];

    while i < n {
        if j < n && ab[i].0 < ab[j].0 + x {
            seq.push(j);
            fin[j] = true;
            used[ab[j].1] = true;

            let last_score = *scores.last().unwrap();
            scores.push(last_score + ab[j].0 + x);
            if i == j {
                i += 1;
            }
            while j < n && used[ab[j].1] {
                j += 1;
            }
        } else {
            seq.push(i);
            fin[i] = true;

            let last_score = *scores.last().unwrap();
            scores.push(last_score + ab[i].0);
            while i < n && fin[i] {
                i += 1;
            }
        }
    }

    let ans = c.iter().map(|&ci| scores[ci]).sum::<usize>();
    println!("{}", ans);
}