#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
using mint = modint998244353;
const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
int op(int a, int b) { return a + b; }
int e() { return 0; }
// combination mod prime
// https://www.youtube.com/watch?v=8uowVvQ_-Mo&feature=youtu.be&t=1619
struct combination {
std::vector<mint> fact, ifact;
combination(int n) :fact(n + 1), ifact(n + 1) {
assert(n < mod);
fact[0] = 1;
for (int i = 1; i <= n; ++i) fact[i] = fact[i - 1] * i;
ifact[n] = fact[n].inv();
for (int i = n; i >= 1; --i) ifact[i - 1] = ifact[i] * i;
}
mint operator()(int n, int k) { return com(n, k); }
mint com(int n, int k) {
//負の二項係数を考慮する場合にコメントアウトを外す
//if (n < 0) return com(-n, k) * (k % 2 ? -1 : 1);
if (k < 0 || k > n) return 0;
return fact[n] * ifact[k] * ifact[n - k];
}
mint comsub(long long n, long long k) {
if (n - k < k) k = n - k;
assert(k < (int)fact.size());
mint val = ifact[k];
for (int i = 0; i < k; ++i) val *= n - i;
return val;
}
template <typename ...Ms, std::enable_if_t<std::conjunction_v<std::is_integral<Ms>...>, std::nullptr_t> = nullptr>
mint polynom(const int n, const Ms & ...ms) {
mint res = fact[n];
int sum = 0;
for (int m : { ms... }) {
if (m < 0 or m > n) return 0;
res *= ifact[m];
sum += m;
}
if (sum > n)return 0;
res *= ifact[n - sum];
return res;
}
mint div(int x) {
if (x >= (int)fact.size())return mint(x).inv();
return fact[x - 1] * ifact[x];
}
mint inv(int n, int k) {
//if (n < 0) return inv(-n, k) * (k % 2 ? -1 : 1);
if (k < 0 || k > n) return 0;
return ifact[n] * fact[k] * fact[n - k];
}
mint p(int n, int k) { return fact[n] * ifact[n - k]; }
}c(2000006);
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int n, d; cin >> n >> d;
map<int, int>mp;
rep(i, n) {
int a; cin >> a;
mp[a - 1]++;
}
segtree<int, op, e>seg(1000000);
mint ans = 1;
for (auto[k, v] : mp) {
int cnt = seg.prod(max(0, k - d), k);
mint tmp = c(cnt + v, v);
ans *= tmp;
seg.set(k, v);
}
cout << ans.val() << endl;
return 0;
}