import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        String string = br.readLine();
        int length = string.length();
        String[] input = br.readLine().split(" ");
        int[] values = new int[length];

        for (int i = 0; i < length; i++) {
            values[i] = Integer.parseInt(input[i]);
        }

        int res = 0;
        int lastDigit = string.charAt(0) - '0';
        int previousValue = values[0];

        for (int i = 1; i < length; i++) {
            int currentDigit = string.charAt(i) - '0';
            if (currentDigit == lastDigit) {
                res += Math.min(previousValue, values[i]);
                previousValue = Math.max(previousValue, values[i]);
            } else {
                lastDigit = currentDigit;
                previousValue = values[i];
            }
        }

        System.out.println(res);
    }
}