N=int(input())
S=input()
A=list(map(int,input().split()))

DP=[1<<60]*(2*N+1)
DP[0]=0
for j in range(2*N):
    s=S[j]
    NDP=[1<<60]*(2*N+1)

    if s=="(":
        for i in range(2*N):
            NDP[i+1]=min(NDP[i+1],DP[i])

        for i in range(1,2*N+1):
            NDP[i-1]=min(NDP[i-1],DP[i]+A[j])
    else:
        for i in range(2*N):
            NDP[i+1]=min(NDP[i+1],DP[i]+A[j])

        for i in range(1,2*N+1):
            NDP[i-1]=min(NDP[i-1],DP[i])

    DP=NDP

print(DP[0])