#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;

#define eb emplace_back
#define all(s) (s).begin(), (s).end()
#define rep(i, a, b) for (int i = (a); i <= (b); ++i)
#define per(i, a, b) for (int i = (a); i >= (b); --i)

#define bs 31
#define mod 998244353
#define mod1 1000000007
#define mod2 1000000009

#define N 1000007

char s[N], t[N];

int n, m, pw1[N], pw2[N], ans[3][N], sum[3][N];

vector<pii> hs, ht;

int main() {
    pw1[0] = pw2[0] = 1;
    rep(i, 1, N - 1) {
        pw1[i] = 1ll * pw1[i - 1] * bs % mod1;
        pw2[i] = 1ll * pw2[i - 1] * bs % mod2;
    }
    auto hash = [&](char* s, vector<pii> &h, int &len) {
        h.eb(0, 0);
        len = strlen(s + 1);
        int h1 = 0, h2 = 0;
        rep(i, 1, len) {
            h1 = (1ll * h1 * bs + s[i] - 'a') % mod1;
            h2 = (1ll * h2 * bs + s[i] - 'a') % mod2;
            h.eb(h1, h2);
        }
    };
    auto gethash = [&](vector<pii> &h, int l, int r) {
        int h1 = ((h[r].first - 1ll * h[l - 1].first * pw1[r - l + 1]) % mod1 + mod1) % mod1;
        int h2 = ((h[r].second - 1ll * h[l - 1].second * pw2[r - l + 1]) % mod2 + mod2) % mod2;
        return make_pair(h1, h2);
    };
    auto mo = [&](int x) {return x >= mod ? x - mod : x;};
    scanf("%s", s + 1); hash(s, hs, n);
    scanf("%s", t + 1); hash(t, ht, m);
    ans[0][n + 1] = ans[1][n + 1] = sum[0][n + 1] = sum[1][n + 1] = 1;
    per(i, n, 1) {
        // find max R
        int l, r, R = min(i + m - 1, n);
        if (gethash(hs, i, R) != gethash(ht, 1, R - i + 1)) {
            if (s[i] != t[1]) l = i - 1;
            else {
                l = i; r = R;
                while (l < r) {
                    int mid = (l + r + 1) / 2;
                    gethash(hs, i, mid) == gethash(ht, 1, mid - i + 1) ? l = mid : r = mid - 1;
                }
            }
            if (l + 2 <= R) {
                if (s[l + 2] != t[l + 3 - i]) R = l + 1;
                else {
                    int pos = l + 2;
                    l = pos; r = R;
                    while (l < r) {
                        int mid = (l + r + 1) / 2;
                        gethash(hs, pos, mid) == gethash(ht, pos - i + 1, mid - i + 1) ? l = mid : r = mid - 1;
                    }
                    R = l;
                }
            }
        }
        per(k, 2, 0) ans[k][i] = mo(sum[k][i + 1] + mod - sum[k][R + 2]);
        ans[2][i] = mo(ans[2][i] + ans[1][i]);
        ans[1][i] = mo(ans[1][i] + mo(ans[0][i] << 1));
        per(k, 2, 0) sum[k][i] = mo(sum[k][i + 1] + ans[k][i]);
    }
    printf("%d\n", ans[2][1]);
    return 0;
}