N = gets.to_i
S = gets.chomp
A = gets.split.map(&:to_i)

cur = Array.new(2) { Array.new(2, 0) }
ans = -Float::INFINITY

A.zip(S.chars) do |a, s|
  2.times do |i|
    r, b = cur[i]
    v = (r - b).abs

    nr = (s == 'R') ? r + a : r
    nb = (s == 'B') ? b + a : b
    nv = (nr - nb).abs
    ans = nv if ans < nv

    if i == 0
      if nr >= nb
        cur[i] = [nr, nb]
      else
        cur[i] = [0, 0]
      end
    else
      if nr <= nb
        cur[i] = [nr, nb]
      else
        cur[i] = [0, 0]
      end
    end
  end
end

puts ans