import java.io.*;
import java.util.*;

public class B_TwoColorSequence {
    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    private static StringTokenizer st;

    private static int readInt() throws IOException {
        while (st == null || !st.hasMoreTokens()) st = new StringTokenizer(br.readLine());
        return Integer.parseInt(st.nextToken());
    }

    public static void main(String[] args) throws IOException {
        int N = readInt();
        String paint = br.readLine();
        int[] a = new int[N];
        for (int i = 0; i < N; i++) a[i] = readInt()
                * (paint.charAt(i) == 'R' ? -1 : 1);

        long answer = 0;
        long maxPos = Math.max(0, a[0]);
        long minNeg = Math.min(0, a[0]);
        for (int i = 1; i < N; i++) {
            maxPos = Math.max(maxPos + a[i], 0);
            answer = Math.max(answer, maxPos);
            minNeg = Math.min(minNeg + a[i], 0);
            answer = Math.max(answer, -minNeg);
        }

        System.out.println(answer);
    }
}