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

int main() {
    int N;
    string S;
    cin >> N >> S;
    vector<int>A(N);
    vector<long long>sum(N+1);
    for(int i = 0; i < N; i++) {
        cin >> A[i];
        if(S[i] == 'R') {
            sum[i+1] = sum[i]+A[i];
        }
        else {
            sum[i+1] = sum[i]-A[i];
        }
    }
    sort(sum.begin(),sum.end());
    cout << sum[N]-sum[0] << endl;
}