#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <array>
#include <atcoder/modint>

using namespace std;
using i32 = int32_t;
using u32 = uint32_t;
using i64 = int64_t;
using u64 = uint64_t;
#define rep(i,n) for(int i=0; i<(int)(n); i++)


const i64 INF = 1001001001001001001;
using modint = atcoder::static_modint<998244353>;

using Matrix = std::array<modint, 3>;

Matrix mult(Matrix l, Matrix r){
    Matrix res;
    rep(i,3) rep(j,3) res[(i+j)%3] += l[i] * r[j];
    return res;
}

Matrix add(Matrix l, Matrix r){
    Matrix res;
    rep(i,3) res[i] = l[i] + r[i];
    return res;
}

int main(){
    int N; cin >> N;
    string S; cin >> S;
    
    modint ans = 0;
    Matrix pre;
    rep(i,N){
        pre[0] += 1;
        Matrix mat;
        if(S[i] == '?') mat = {4,3,3}; else mat[(S[i]-'0')%3] = 1;
        pre = mult(pre, mat);
        ans += pre[0];
    }

    cout << ans.val() << '\n';
    return 0;
}


struct ios_do_not_sync{
    ios_do_not_sync(){
        std::ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
    }
} ios_do_not_sync_instance;