Find a RedSpica

from collections import deque 

​

N=int(input())

b=list(map(int,input().split()))

c=list(input().split())

​

M=int(input())

g=[[] for _ in range(N)]

for i in range(M):

    x,y=map(int,input().split())

    g[x-1].append(y-1)

    g[y-1].append(x-1)

​

Q=deque()

check=set()

ans=0

for x in range(N):

    if x in check:

        continue

    bright,color=b[x],c[x]

    Q.append(x)

    check.add(x)

    while len(Q):

        now=Q.popleft()

        for i in range(len(g[now])):

            nex=g[now][i]

            if nex in check:

                continue

            if b[nex]>bright:

                bright=b[nex]

                color=c[nex]

​

            Q.append(nex)

            check.add(nex)

​

    if color=='R':

        ans+=1

​

print(ans)