n = int(input())
S = str(input())
A = list(map(int, input().split()))
for i, a in enumerate(A):
    if S[i] == 'R':
        A[i] = a
    else:
        A[i] = -a

INF = 10**18
dp1 = [-INF]*(n+1)
for i in range(n):
    dp1[i+1] = max(A[i], dp1[i]+A[i])
ans1 = max(0, max(dp1[1:]))
dp2 = [INF]*(n+1)
for i in range(n):
    dp2[i+1] = min(A[i], dp2[i]+A[i])
ans2 = min(0, min(dp2[1:]))
print(max(abs(ans1), abs(ans2)))