#include <bits/stdc++.h>
using namespace std;
using ll = long long;

template<class T> istream& operator >> (istream& is, vector<T>& vec) {
    for(T& x : vec) is >> x;
    return is;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    string s;
    cin >> n >> s;
    n *= 2;
    vector<ll> a(n);
    cin >> a;
    vector<vector<ll>> dp(n + 1, vector<ll>(n + 1, 1ll << 60));
    dp[0][0] = 0;
    for(int i = 0; i < n; i++){
        dp[i + 1][1] = min(dp[i + 1][1], dp[i][0] + (s[i] == ')' ? a[i] : 0));
        for(int j = 1; j <= i; j++){
            dp[i + 1][j + 1] = min(dp[i + 1][j + 1], dp[i][j] + (s[i] == ')' ? a[i] : 0));
            dp[i + 1][j - 1] = min(dp[i + 1][j - 1], dp[i][j] + (s[i] == '(' ? a[i] : 0));
        }
    }
    cout << dp[n][0] << '\n';
}