n = int(input())
s = input()
a = list(map(int, input().split()))
ans = 0
r = 0
b = 0

for i in range(n):
    if s[i] == 'R':
        r = max(a[i], r + a[i])
        b = max(-a[i], b - a[i])
    else:
        r = max(-a[i], r - a[i])
        b = max(a[i], b + a[i])
    ans = max(ans, r, b)

print(ans)