N=int(input())
S=input().strip()
mod=998244353

if S[0]=="?":
    DP=[4,3,3]
else:
    x=int(S[0])
    DP=[0,0,0]
    DP[x%3]=1

ANS=0
for s in S[1:]:
    ANS+=DP[0]
    ANS%=mod
    if s=="?":
        NDP=[4,3,3]

        for i in range(3):
            NDP[i]+=DP[i]*4
            NDP[(i+1)%3]+=DP[i]*3
            NDP[(i+2)%3]+=DP[i]*3
    else:
        x=int(s)
        NDP=[0,0,0]

        NDP[x%3]=1

        for i in range(3):
            NDP[(i+x)%3]+=DP[i]

    for i in range(3):
        DP[i]=NDP[i]%mod

print((ANS+DP[0])%mod)