#include <bits/stdc++.h>
#define rep(i,a,b) for(int i=(a);i<=(b);++i)
#define per(i,a,b) for(int i=(a);i>=(b);--i)

using namespace std;

const int N = 1e6 + 10, mod = 998244353;
inline int inc(int x, int y) { return (x += y) < mod ? x : x - mod; }
inline int dec(int x, int y) { return (x -= y) < 0 ? x + mod : x; }
inline int mul(int x, int y) { return 1ll * x * y % mod; }
char s[N << 1];
int sa[N << 1], rk[N << 1], ht[N << 1];

void buildSA(char *s, int *sa, int *rk, int *ht, int n, int m = 128) {
    static int x[N << 2], y[N << 2], c[N << 1];
    rep(i,1,n) x[i] = s[i] + 1;
    rep(i,1,m) c[i] = 0;
    rep(i,1,n) ++ c[x[i]];
    rep(i,2,m) c[i] += c[i - 1];
    per(i,n,1) sa[c[x[i]] --] = i;
    for(int k = 1; k <= n && n != m; k <<= 1) {
        int p = 0;
        rep(i,n-k+1,n) y[++ p] = i;
        rep(i,1,n) if(sa[i] > k) y[++ p] = sa[i] - k;
        rep(i,1,m) c[i] = 0;
        rep(i,1,n) ++ c[x[i]];
        rep(i,2,m) c[i] += c[i - 1];
        per(i,n,1) sa[c[x[y[i]]] --] = y[i];
        swap(x, y);
        p = 1; x[sa[1]] = 1;
        rep(i,2,n)
            if(y[sa[i]] == y[sa[i - 1]] && y[sa[i] + k] == y[sa[i - 1] + k])
                x[sa[i]] = p;
            else x[sa[i]] = ++ p;
        m = p;
    }
    rep(i,1,n) rk[sa[i]] = i;
    int k = 0;
    rep(i,1,n) {
        if(rk[i] == 1) continue;
        while(s[i + k] == s[sa[rk[i] - 1] + k]) ++ k;
        ht[rk[i]] = k;
        k = max(k - 1, 0);
    }
}

int ST[22][N << 1];
void buildST(int n) {
    rep(i,1,n) ST[0][i] = ht[i];
    for(int d = 1, len = 2; len <= n; ++ d, len <<= 1)
        for(int l = 1; l + len - 1 <= n; ++ l)
            ST[d][l] = min(ST[d - 1][l], ST[d - 1][l + len / 2]);
}
int qry(int l, int r) {
    int d = 31 - __builtin_clz(r - l + 1);
    return min(ST[d][l], ST[d][r - (1 << d) + 1]);
}

inline int getRside(int i, int n, int m) {
    int x = rk[i], y = rk[n + 2];
    if(x > y) swap(x, y);
    int len1 = qry(x + 1, y);
    // cout << x2 << ' ' << y2 << endl;
    int x2 = i + len1 + 1, y2 = n + 3 + len1;
    x2 = rk[x2], y2 = rk[y2];
    if(x2 > y2) swap(x2, y2);
    int len2 = qry(x2 + 1, y2);
    return i + min(len1 + len2, min(n - i, m - 1));
}

int f[N][3];

signed main() {
    scanf("%s", s + 1);
    int n = strlen(s + 1);
    s[n + 1] = '#';
    scanf("%s", s + n + 2);
    int m = strlen(s + n + 2);
    // cout << (s + 1) << endl;
    buildSA(s, sa, rk, ht, n + m + 1);
    // rep(i,1,n + m + 1) cout << sa[i] <<  ' ';
    // cout << endl;
    // rep(i,1,n + m + 1) cout << ht[i] << ' ';
    // cout << endl;
    buildST(n + m + 1);
    // cout << qry(6, 7) << ' ' << qry(5, 7) << ' ' << qry(4, 7) << endl;
    f[n + 1][0] = 1; f[n + 1][1] = f[n + 1][2] = 0;
    // rep(i,1,n) cout << getRside(i, n, m) << ' ';
    // cout << endl;
    // getRside(1, n, m);
    // return 0;
    per(i,n,1) {
        int rside = getRside(i, n, m);
        f[i][0] = dec(f[i + 1][0], f[rside + 2][0]);
        f[i][1] = inc(f[i][0], dec(f[i + 1][1], f[rside + 2][1]));
        f[i][2] = inc(inc(f[i][0], mul(2, dec(f[i + 1][1], f[rside + 2][1]))), dec(f[i + 1][2], f[rside + 2][2]));
        // f[i][0] = f[i + 1][0] - f[rside + 2][0];
        // f[i][1] = f[i][0] + f[i + 1][1] - f[rside + 2][1];
        // f[i][2] = f[i][0] + 2 * (f[i + 1][1] - f[rside + 2][1]) + f[i + 1][2] - f[rside + 2][2];
        f[i][0] = inc(f[i][0], f[i + 1][0]);
        f[i][1] = inc(f[i][1], f[i + 1][1]);
        f[i][2] = inc(f[i][2], f[i + 1][2]);
        // f[i][0] += f[i + 1][0];
        // f[i][1] += f[i + 1][1];
        // f[i][2] += f[i + 1][2];
    }
    // rep(i,1,n) cout << dec(f[i][2], f[i + 1][2]) << ' ';
    // cout << endl;
    // rep(i,1,n) cout << dec(f[i][1], f[i + 1][1]) << ' ';
    // cout << endl;
    // rep(i,1,n) cout << dec(f[i][0], f[i + 1][0]) << ' ';
    // cout << endl;
    cout << dec(f[1][2], f[2][2]) << endl;

    // rep(i,1,n + 1) cout <<  f[i][2] << '\t';
    // cout << endl;
    // rep(i,1,n + 1) cout <<  f[i][1] << '\t';
    // cout << endl;
    // rep(i,1,n + 1) cout <<  f[i][0] << '\t';
    // cout << endl;

    return 0;
}