#!/usr/bin/env python3
import sys

def main():
    import itertools 
    N = int(input())
    S = input()
    A = list(map(int, input().split()))
    RmB = []
    mRB = []
    for i in range(N):
        if S[i] == "B":
            RmB.append(-A[i])
            mRB.append(A[i])
        else:
            RmB.append(A[i])
            mRB.append(-A[i])
    sRmB = [0] + list(itertools.accumulate(RmB))
    smRB = [0] + list(itertools.accumulate(mRB))
    # print(RmB)
    # print(mRB)
    # print(sRmB)
    # print(smRB)
    minS = 10 ** 10
    maxS = -1 * 10 ** 10
    ans = -1 * 10 ** 10
    for i in range(N + 1):
        # print(sRmB[i], minS)
        if sRmB[i] <= minS:
            ans = max(ans, maxS - minS)
            minS = sRmB[i]
            maxS = -1 * 10 ** 10
        maxS = max(sRmB[i], maxS)
    ans = max(ans, maxS - minS)
    minS = 10 ** 10
    maxS = -1 * 10 ** 10
    for i in range(N + 1):
        # print(smRB[i], minS)
        if smRB[i] <= minS:
            ans = max(ans, maxS - minS)
            minS = smRB[i]
            maxS = -1 * 10 ** 10
        maxS = max(smRB[i], maxS)
    ans = max(ans, maxS - minS)
    print(ans)





    return

if __name__ == '__main__':
    main()