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(); } }