N=int(input())
S=input()
ANS=0
X=[0]*N
mod=998244353
for i in range(N):
  if S[i]=='?':
    X[i]=0
  else:
    X[i]=int(S[i])%3
C=[0]*3
C[0]=1
v=0
for i in range(N):
  v=(v+X[i])%3
  C[v]+=1
for i in range(3):
  ANS=(ANS+(C[i]*(C[i]-1))//2)%mod
P=0
for i in range(N):
  if S[i]=='?':
    P=(P*10+(i+1)*3)%mod
  ANS=(ANS+P)%mod
print(ANS)