func main()
	var n: int :: cui@inputInt()
	var s: []char :: cui@input()
	var a: []int :: #[n]int
	var cum: []int :: #[n + 1]int
	for i(0, n - 1)
		do a[i] :: cui@inputInt() * (s[i] = 'R' ?(1, -1))
		do cum[i + 1] :: cum[i] + a[i]
	end for
	
	var ans: int :: cum.max() - cum.min()
	do cui@print("\{ans}\n")
end func