import sys
input = sys.stdin.readline
N = int(input())
S = list(input())[: -1]
a = list(map(int, input().split()))

scores = [0] * N
for i in range(N):
  if S[i] == "R": scores[i] += a[i]
  else: scores[i] -= a[i]
  if i + 1 < N: scores[i + 1] += scores[i]

inf = 10 ** 15
scmx = [-inf] * N
scmn = [inf] * N
for i in range(N - 1, -1, -1):
  scmx[i] = scores[i]
  scmn[i] = scores[i]
  if i + 1 < N:
    scmx[i] = max(scmx[i], scmx[i + 1])
    scmn[i] = min(scmn[i], scmn[i + 1])

res = abs(scores[-1])
for i in range(N):
  res = max(res, abs(scmx[i] - scores[i]))
  res = max(res, abs(scmn[i] - scores[i]))

print(res)