N=int(input())
A=list(map(int,input().split()))
B=input().split()
mod=998244353
dp=[[[0]*34 for U in range(5)] for c in range(10)]
dp[0][0][0]=1
for a,b in zip(A,B):
    if "X" in b:
        continue
    b=int(b)
    for c in range(9,0,-1):
        for U in range(4,a-1,-1):
            for D in range(33,b-1,-1):
                dp[c][U][D]+=dp[c-1][U-a][D-b]
                dp[c][U][D]%=mod
ans=0
for a,b in zip(A,B):
    if b=="X":
        for U in range(5):
            for D in range(34):
                if (U+a,D)==(4,33):
                    ans+=dp[8][U][D]
                    ans%=mod
print(ans)