fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    let s = s.trim().chars().collect::<Vec<_>>();
    let mut a = String::new();
    std::io::stdin().read_line(&mut a).ok();
    let a: Vec<isize> = a.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();

    let mut summary = vec![0isize; n+1];
    for i in 0..n {
        summary[i+1] = summary[i] + if s[i] == 'R' { a[i] } else { -a[i] };
    }
    let mut minval = 0;
    let mut maxval = 0;
    let mut result = 0isize;
    for i in 0..n {
        minval = minval.min(summary[i+1]);
        maxval = maxval.max(summary[i+1]);
        result = result.max((summary[i+1] - minval).abs());
        result = result.max((summary[i+1] - maxval).abs());
    }
    println!("{}", result);
}