#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  string s;
  ll r, m;
  cin >> n >> s >> r >> m;
  if (n % 2) {
    cout << -1 << '\n';
    return 0;
  }
  VI init(2 * n + 1);
  rep(i, n) {
    init[i+1] = init[i] + (s[i] == '(' ? 1 : -1);
  }
  rep(i, n) {
    init[n+i+1] = init[n+i] + (s[i] == '(' ? 1 : -1);
  }
  constexpr int INF = 1001001001;
  segtree<int, [](int x, int y) { return min(x, y); }, []() { return INF; }> seg(init);
  ll ans = 1e18;
  rrep(l, n + 1) {
    int mn = seg.prod(l, l + n + 1);
    int d = init[l] - mn;
    int cnt = (d + 1) / 2;
    ll cost = cnt * m;
    int last = init[l + n] + 2 * cnt;
    cost += (last - init[l]) / 2 * m;
    cost += (n - l) * r;
    chmin(ans, cost);
  }
  cout << ans << '\n';
}