n = int(input())
s = input().strip()
a = list(map(int, input().split()))

t = []
for i in range(n):
    if s[i] == 'R':
        t.append(a[i])
    else:
        t.append(-a[i])

if n == 0:
    print(0)
    exit()

current_max = max_sum = t[0]
current_min = min_sum = t[0]

for i in range(1, n):
    current_max = max(t[i], current_max + t[i])
    max_sum = max(max_sum, current_max)
    current_min = min(t[i], current_min + t[i])
    min_sum = min(min_sum, current_min)

result = max(abs(max_sum), abs(min_sum))
print(result)