#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
long long a[200020];
long long sum[200020] = {};
int main() {
	int n;
	string s;
	cin >> n >> s;
	if (n == 1) {
		cin >> a[0];
		cout << a[0] << endl;
		return 0;
	}
	long long ans = -100000000000007, ma = 0, mi = 0;
	for (int i = 0; i < n; i++) {
		cin >> a[i];
		if (s[i] == 'R') {
			sum[i] -= a[i];
		}
		else {
			sum[i] += a[i];
		}
		if (i != 0) {
			sum[i] += sum[i - 1];
			if (abs(sum[i] - ma) > ans) {
				ans = abs(sum[i] - ma);
			}
			if (abs(sum[i] - mi) > ans) {
				ans = abs(sum[i] - mi);
			}
		}
		if (ma < sum[i]) {
			ma = sum[i];
		}
		if (mi > sum[i]) {
			mi = sum[i];
		}
	}
	cout << ans << endl;
}