import sys
input = sys.stdin.readline
from collections import *

N = int(input())
S = input()[:-1]
a = list(map(int, input().split()))
m, M = 0, 0
now = 0
ans = -10**18

for i in range(N):
    if S[i]=='R':
        now += a[i]
    else:
        now -= a[i]
    
    ans = max(ans, abs(now-m), abs(M-now))
    m = min(m, now)
    M = max(M, now)

print(ans)