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

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        char[] colors = sc.next().toCharArray();
        long[] sums = new long[n + 1];
        for (int i = 1; i <= n; i++) {
            sums[i] = sums[i - 1];
            int x = sc.nextInt();
            if (colors[i - 1] == 'R') {
                sums[i] += x;
            } else {
                sums[i] -= x;
            }
        }
        Arrays.sort(sums);
        System.out.println(sums[n] - sums[0]);
    }
}

class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}