package main

import . "fmt"

func main() {
	var n int
	var s string
	Scan(&n, &s)
	a := make([]int, 2*n)
	for i := range a {
		Scan(&a[i])
	}
	dp := make([][]int, 2*n+1)
	for i := range dp {
		dp[i] = make([]int, n+1)
		for j := range dp[i] {
			dp[i][j] = 1e18
		}
	}
	dp[0][0] = 0
	for i, c := range s {
		for j, x := range dp[i] {
			if c == '(' {
				if j+1 <= n {
					dp[i+1][j+1] = min(dp[i+1][j+1], x)
				}
				if j > 0 {
					dp[i+1][j-1] = min(dp[i+1][j-1], x+a[i])
				}
			} else {
				if j+1 <= n {
					dp[i+1][j+1] = min(dp[i+1][j+1], x+a[i])
				}
				if j > 0 {
					dp[i+1][j-1] = min(dp[i+1][j-1], x)
				}
			}
		}
	}
	Println(dp[2*n][0])
}