#include using namespace std; void fast_io() { ios_base::sync_with_stdio(false); cin.tie(nullptr); } #include using mint = atcoder::modint998244353; int main() { fast_io(); string s, t; cin >> s >> t; int n = s.size(), m = t.size(); mint dp[n + 1][m + 1] = {}; dp[0][0] = 1; for (int i = 0; i < n; i++) { for (int j = 0; j <= m; j++) { if (j < m && s[i] == t[j]) { dp[i + 1][j + 1] += dp[i][j]; } dp[i + 1][j] += dp[i][j]; } } mint ans = dp[n][m] * mint(2).pow(n - m); cout << ans.val() << endl; }