N=int(input())
S=input()
A=list(map(int,input().split()))
dp=[0]*N
if S[0]=="R":
  dp[0]=max(A[0],0)
else:
  dp[0]=max(-A[0],0)
for i in range(1,N):
  if S[i]=="R":
    dp[i]=max(dp[i-1]+A[i],A[i])
  else:
    dp[i]=max(dp[i-1]-A[i],-A[i])
ans=max(dp)
dp=[0]*N
if S[0]=="B":
  dp[0]=max(A[0],0)
else:
  dp[0]=max(-A[0],0)
for i in range(1,N):
  if S[i]=="R":
    dp[i]=max(dp[i-1]-A[i],-A[i])
  else:
    dp[i]=max(dp[i-1]+A[i],A[i])
ans=max(ans,max(dp))
print(ans)