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

const int mod=998244353;

struct BIT{
    int n;
    vector<int>tr;
    BIT(int n=0):n(n){tr=vector<int>(n+1,0);}
	inline void resize(int m){
        n=m;
        tr.resize(m+1);
    }
    inline int lowbit(int x){return x&-x;}
    inline void add(int x,int y){
        if(y<0)y+=mod;
        for(;x<=n;x+=lowbit(x))(tr[x]+=y)%=mod;
    }
    inline int pre(int x){
        if(x<=0)return 0;
        int res=0;
        for(;x;x-=lowbit(x))(res+=tr[x])%=mod;
        return res;
    }
    inline int query(int l,int r){
        return (pre(r)-pre(l-1)+mod)%mod;
    }
    inline int suf(int x){
        return query(x,n);
    }
};

const int P1=13331,mod1=1610612741;
const int P2=49999,mod2=1000000007;
const int N=1e6+6;

int p1[N],h1[2][N];
int p2[N],h2[2][N];
string s,t;
int n,m;

inline int get(int l,int r,int i){
    if(i==0&&r>n)return -1;
    if(i==1&&r>m)return -2;

    return (h1[i][r]-h1[i][l-1]*p1[r-l+1]%mod1+mod1)%mod1
    +(h2[i][r]-h2[i][l-1]*p2[r-l+1]%mod2+mod2)%mod2;
}


signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);

    cin>>s>>t;
    n=s.size(),m=t.size();
    s=" "+s,t=" "+t;

    p1[0]=p2[0]=1;
    for(int i=1;i<=max(n,m);i++){
        p1[i]=p1[i-1]*P1%mod1;
        p2[i]=p2[i-1]*P2%mod2;
    }

    for(int i=1;i<=n;i++){
        h1[0][i]=(h1[0][i-1]*P1+s[i])%mod1;
        h2[0][i]=(h2[0][i-1]*P2+s[i])%mod2;
    }

    for(int i=1;i<=m;i++){
        h1[1][i]=(h1[1][i-1]*P1+t[i])%mod1;
        h2[1][i]=(h2[1][i-1]*P2+t[i])%mod2;
    }

    vector<int>R(n+1);
    for(int i=1;i<=n;i++){
        int l=i,r=min(n,i+m-1);

        while(l<r){
            int mid=l+r+1>>1;
            if(get(i,mid,0)==get(1,mid-i+1,1))l=mid;
            else r=mid-1;
        }

        if(l==n||l==i+m-1){
            R[i]=l;
            continue;
        }

        int ans=l;
        if(get(i,ans,0)==get(1,ans-i+1,1))ans++;//* 前面完全匹配, ans+1 不匹配

        R[i]=ans;

        if(ans==n||ans==i+m-1)continue;

        int len=ans-i+1;
        if(s[ans+1]==t[len+1]){//* 继续向后看 s[ans+1...]与 t[len+1...] 能否完全匹配
            l=ans+1,r=min(n,i+m-1);

            while(l<r){
                int mid=l+r+1>>1;
                if(get(ans+1,mid,0)==get(len+1,mid-i+1,1))l=mid;
                else r=mid-1;
            }

            R[i]=l;
        }
    }

    vector<BIT>tr(3,BIT(n+10));

    for(int i=1;i<=n;i++){
        int a=tr[0].pre(i-1),b=tr[1].pre(i-1),c=tr[2].pre(i-1);
        if(i==1)c++;

        int v0=((a+b*2%mod)%mod+c)%mod;
        tr[0].add(i,v0),tr[0].add(R[i]+1,-v0);

        int v1=(b+c)%mod;
        tr[1].add(i,v1),tr[1].add(R[i]+1,-v1);

        int v2=c;
        tr[2].add(i,v2),tr[2].add(R[i]+1,-v2);
    }

    cout<<tr[0].pre(n)<<"\n";
    return 0;
}