def main1(n,s,a):
    ans=-float('inf')
    """
    |R-B|=max(R-B,B-R)
    """
    b=[ai if si=='R' else -ai for ai,si in zip(a,s)]
    # bの連続部分列和の最大
    sb=[0]
    for x in b:sb.append(sb[-1]+x)
    m=0
    for x in sb[1:]:
        ans=max(ans,x-m)
        m=min(m,x)
    b=[-ai if si=='R' else ai for ai,si in zip(a,s)]
    # bの連続部分列和の最大
    sb=[0]
    for x in b:sb.append(sb[-1]+x)
    m=0
    for x in sb[1:]:
        ans=max(ans,x-m)
        m=min(m,x)
    return ans

if __name__=='__main__':
    n=int(input())
    s=list(input())
    a=list(map(int,input().split()))
    print(main1(n,s,a))