import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int r = sc.nextInt(), y = sc.nextInt(), g = sc.nextInt(), n = sc.nextInt();
        int res = 0;
        while (n-- > 0) {
            int k = sc.nextInt(), t = sc.nextInt();
            if (k == 0) res += t;
            else if (k == 1) res += t;
            else if (k == 2) res += t + r;
        }
        System.out.println(res);
    }
}