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

#define INF_LL (int64)1e18
#define INF (int32)1e9
#define REP(i, n) for(int64 i = 0;i < (n);i++)
#define FOR(i, a, b) for(int64 i = (a);i < (b);i++)
#define all(x) x.begin(),x.end()
#define fs first
#define sc second

using int32 = int_fast32_t;
using uint32 = uint_fast32_t;
using int64 = int_fast64_t;
using uint64 = uint_fast64_t;
using PII = pair<int32, int32>;
using PLL = pair<int64, int64>;

const double eps = 1e-10;

template<typename A, typename B>inline void chmin(A &a, B b){if(a > b) a = b;}
template<typename A, typename B>inline void chmax(A &a, B b){if(a < b) a = b;}

const int64 mod = 1e9+7;

int main(void){
	cin.tie(0);
	ios::sync_with_stdio(false);
	int64 N, K;
	vector<int64> A;
	cin >> N >> K;
	A.resize(N);
	for(auto &x : A) cin >> x;
	sort(all(A));
	int64 r = 0, used = 0;
	int64 res = 1;
	for (int64 i = N-1; i >= 0; i--) {
		while(r <= i && A[r] + A[i] <= K) r++;
		if (r > i) break;
		res *= (r-used);
		res %= mod;
		used++;
	}
	for (int64 i = r-used; i > 0; i-=2) {
		res *= i-1;
		res %= mod;
	}
	cout << res << endl;
}