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

public class Main {
    static int n;
    static int[] values;
    static long[][] dp;
    static char[] inputs;
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        n = sc.nextInt();
        inputs = sc.next().toCharArray();
        values = new int[n * 2];
        for (int i = 0; i < n * 2; i++) {
            values[i] = sc.nextInt();
        }
        dp = new long[n * 2][n + 1];
        for (long[] arr : dp) {
            Arrays.fill(arr, -1);
        }
        System.out.println(dfw(n * 2 - 1, 0));
    }
    
    static long dfw(int idx, int v) {
        if (v < 0 || v > n) {
            return Long.MAX_VALUE / 2;
        }
        if (idx < 0) {
            if (v == 0) {
                return 0;
            } else {
                return Long.MAX_VALUE / 2;
            }
        }
        if (dp[idx][v] < 0) {
            if (inputs[idx] == ')') {
                dp[idx][v] = Math.min(dfw(idx - 1, v + 1), dfw(idx - 1, v - 1) + values[idx]);
            } else {
                dp[idx][v] = Math.min(dfw(idx - 1, v - 1), dfw(idx - 1, v + 1) + values[idx]);
            }
        }
        return dp[idx][v];
    }
}
class Utilities {
    static String arrayToLineString(Object[] arr) {
        return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));
    }
    
    static String arrayToLineString(int[] arr) {
        return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    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 int[] nextIntArray() throws Exception {
        return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}