#include <bits/stdc++.h>
using namespace std;

constexpr int mod = 998244353;

int dp[200200][3];

int main() {
    int N;
    string S;
    cin >> N >> S;
    dp[0][0] = 1;
    int ans = 0;
    for(int i = 0; i < N; i++) {
        for(int j = 0; j < 3; j++) {
            if(S[i] == '?') {
                for(int k = 0; k < 3; k++) {
                    dp[i+1][(j+k)%3] += 1ll*dp[i][j]*((k == 0)?4:3)%mod;
                    if(dp[i+1][(j+k)%3] >= mod) dp[i+1][(j+k)%3] -= mod;
                }
            }
            else {
                dp[i+1][(j+S[i]-'0')%3] += dp[i][j];
                if(dp[i+1][(j+S[i]-'0')%3] >= mod) dp[i+1][(j+S[i]-'0')%3] -= mod;
            }
        }
        ans += dp[i+1][0];
        if(ans >= mod) ans -= mod;
        dp[i+1][0]++;
        if(dp[i+1][0] >= mod) dp[i+1][0] -= mod;
    }
    cout << ans << endl;
}