E

#include <bits/stdc++.h>

using namespace std;

#define ll     long long

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    ll int MOD = 998244353;

    function <ll int (ll int, ll int)> pow = [&](ll int base, ll int exp)
    {
        ll int res = 1;

        while(exp)
        {
            if(exp%2)
                (res *= base) %= MOD;

            (base *= base) %= MOD;
            exp /= 2;
        }

        return res;
    };

    ll int n, x;
    cin>>n>>x;

    vector<ll int> t(n);
    for(auto &e: t)   cin>>e;

    vector<ll int> prob(x+1);

    ll int inv = pow(n, MOD-2);
    vector<ll int> prob2(x+1);
    prob[0] = inv;

    for(int i=0; i<n; i++)
    {
        (prob2[t[i]] += inv) %= MOD;
    }

    for(int j=1; j<=x; j++)
    {
        (prob[j] += (inv * 1ll * prob2[j])) %= MOD;
        for(int i=0; i<n; i++)
        {

            if(t[i] + j <= x)
                (prob2[t[i]+j] += (prob2[j]*inv)) %= MOD;
        }
    }

    ll int ans = 0;
    for(int j=x; j>max(x-t[0], -1ll); j--)
        (ans += prob[j]) %= MOD;

    cout<<ans<<"\n";
}