#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <utility>
using namespace std;


vector<int> ZAlgorithm(const string& S) {
    int n = S.size();
    vector<int> res(n, 0);
    res[0] = n;
    int pbegin = 1, pend = 1;
    for (int i = 1; i < n; i++) {
        if (i < pend) {
            res[i] = res[i - pbegin];
            if (pend > i + res[i]) continue;
            res[i] = pend - i;
            pbegin = i;
        }
        else {
            pbegin = pend = i;
        }
        while (true) {
            if (pend == n) break;
            if (S[pend] != S[res[i]]) break;
            res[i]++;
            pend++;
        }
    }
    return res;
}


int countT(const string& s, const string& t){
    auto z = ZAlgorithm(t + s);
    int ans = 0;
    for(size_t i=t.size(); i<z.size(); i++) if(z[i] >= (int)t.size()) ans++;
    return ans;
}

const int MOD = 998244353;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N; cin >> N;
    string T; cin >> T;
    
    vector<long long> dp(N);
    vector<string> pre(N);
    vector<string> suf(N);
    vector<bool> tooshort(N, false);

    for(int i=0; i<N; i++){
        string key; cin >> key;
        if(key == "~"){
            int j, k; cin >> j >> k; j--; k--;
            if(tooshort[j]){
                if(tooshort[k]){
                    string q = pre[j] + pre[k];
                    if(q.size() < T.size()){
                        pre[i] = q;
                        tooshort[i] = true;
                    }
                    else{
                        pre[i] = q.substr(0, T.size()-1);
                        suf[i] = q.substr(q.size() - T.size() + 1);
                        dp[i] = countT(q, T);
                    }
                }
                else{
                    string q = pre[j] + pre[k];
                    pre[i] = q.substr(0, T.size()-1);
                    suf[i] = suf[k];
                    dp[i] = (countT(q, T) + dp[k]) % MOD;
                }
            }
            else{
                if(tooshort[k]){
                    string q = suf[j] + pre[k];
                    pre[i] = pre[j];
                    suf[i] = q.substr(q.size() - T.size() + 1);
                    dp[i] = (countT(q, T) + dp[j]) % MOD;
                }
                else{
                    pre[i] = pre[j];
                    suf[i] = suf[k];
                    dp[i] = (dp[j] + dp[k] + countT(suf[j] + pre[k], T)) % MOD;
                }
            }
        }
        else{
            if(key.size() < T.size()){
                pre[i] = key;
                tooshort[i] = true;
            }
            else{
                pre[i] = key.substr(0, T.size() - 1);
                suf[i] = key.substr(key.size() - T.size() + 1);
                dp[i] = countT(key, T);
                tooshort[i] = false;
            }
        }
    }
    
    cout << dp[N-1] << '\n';
    return 0;
}