#include "bits/stdc++.h"

using namespace std;
using ll = long long;
using P = pair<ll, ll>;
const ll INF = (1LL << 61);
ll mod = 998244353;

signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	ll N; cin >> N;
	string S; cin >> S;
	vector<ll>a(N); for (int i = 0; i < N; i++)cin >> a[i];
	vector<ll>sum(N + 1);
	for (int i = 0; i < N; i++) {
		if (S[i] == 'R') {
			sum[i + 1] = sum[i] + a[i] * (-1);
		}
		else {
			sum[i + 1] = sum[i] + a[i];
		}
	}
	ll ans = 0;
	ll mi = INF, ma = -INF;
	for (int i = 0; i <= N; i++) {
		mi = min(mi, sum[i]);
		ma = max(ma, sum[i]);
	}
	ans = max(ans, ma - mi);
	for (int i = 0; i < N; i++) {
		if (S[i] == 'B') {
			sum[i + 1] = sum[i] + a[i] * (-1);
		}
		else {
			sum[i + 1] = sum[i] + a[i];
		}
	}
	mi = INF, ma = -INF;
	for (int i = 0; i <= N; i++) {
		mi = min(mi, sum[i]);
		ma = max(ma, sum[i]);
	}
	ans = max(ans, ma - mi);
	cout << ans << endl;
	return 0;
}