#include <bits/stdc++.h>
using namespace std;

#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define RFOR(i, a, b) for(int i = (a) - 1; i >= (b); i--)
#define SZ(a) (int)a.size()
#define ALL(a) a.begin(), a.end()
#define PB push_back
#define MP make_pair
#define F first
#define S second

typedef long long LL;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef double db;

int add(int a, int b, int mod)
{
	return a + b < mod ? a + b : a + b - mod;
}

int sub(int a, int b, int mod)
{
	return a - b >= 0 ? a - b : a - b + mod;
}

void updAdd(int& x, int val, int mod)
{
	x += val;
	if (x >= mod)
		x -= mod;
}

void updSub(int& x, int val, int mod)
{
	x -= val;
	if (x < 0)
		x += mod;
}

int mult(int a, int b, int mod)
{
	return (LL)a * b % mod;
}

const int M = 998'244'353;
const int N = 1 << 20;

struct Pair
{
	static constexpr int mod[2] = {1'000'000'007, 1'000'000'009};
	int a[2];
	Pair(int x = 0)
	{
		FOR(i, 0, 2)
			a[i] = x;
	}
	Pair operator+(const Pair& p) const
	{
		Pair res;
		FOR(i, 0, 2)
			res.a[i] = add(a[i], p.a[i], mod[i]);
		return res;
	}
	Pair operator-(const Pair& p) const
	{
		Pair res;
		FOR(i, 0, 2)
			res.a[i] = sub(a[i], p.a[i], mod[i]);
		return res;
	}
	Pair operator*(const Pair& p) const
	{
		Pair res;
		FOR(i, 0, 2)
			res.a[i] = mult(a[i], p.a[i], mod[i]);
		return res;
	}
	bool operator==(const Pair& p) const
	{
		FOR(i, 0, 2)
			if (a[i] != p.a[i])
				return false;
		return true;
	}
};

Pair pw[N];
Pair prefHash[2][N];
int f[N];
int dp[N][3], sum[N][3];

void calcHash(const string& s, int j)
{
	FOR(i, 0, SZ(s))
		prefHash[j][i + 1] = prefHash[j][i] + pw[i] * (s[i] - 'a' + 1);
}

Pair getHash(int j, int l, int r)
{
	return (prefHash[j][r] - prefHash[j][l]) * pw[N - 1 - r];
}

int getLCP(const string& s, int i, const string& t, int j)
{
	int l = 0, r = min(SZ(s) - i, SZ(t) - j) + 1;
	while (r - l > 1)
	{
		int m = (l + r) / 2;
		if (getHash(0, i, i + m) == getHash(1, j, j + m))
			l = m;
		else
			r = m;
	}
	return l;
}

void calcF(const string& s, const string& t)
{
	FOR(i, 0, SZ(s))
	{
		int len = getLCP(s, i, t, 0);
		f[i] = len + 1 + getLCP(s, i + len + 1, t, len + 1);
	}
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout << fixed << setprecision(15);
	string s, t;
	cin >> s >> t;
	pw[0] = 1;
	FOR(i, 1, N)
		pw[i] = pw[i - 1] * 47;
	calcHash(s, 0);
	calcHash(t, 1);
	calcF(s, t);
	dp[0][0] = 1;
	FOR(i, 0, SZ(s))
	{
		FOR(j, 0, 3)
			updAdd(dp[i][j], sum[i][j], M);
		int d[3] = {dp[i][0], add(dp[i][1], dp[i][0], M), add(dp[i][2], add(mult(2, dp[i][1], M), dp[i][0], M), M)};
		FOR(j, 0, 3)
		{
			updAdd(sum[i + 1][j], d[j], M);
			updSub(sum[i + f[i]][j], d[j], M);
		}
	}
	cout << dp[SZ(s)][2] << "\n";
	return 0;
}