#include "bits/stdc++.h"

#pragma warning(disable:4996)
using namespace std;
long long int mod=1e9+7;
pair<long long int, long long int>mul(
	pair<long long int, long long int>&l,
	pair<long long int, long long int>&r) {
	auto p=make_pair(l.first*r.first,l.second*r.first+r.second);
	return make_pair(p.first%mod,p.second%mod);
}


pair<long long int,long long int> solve(pair<long long int,long long int> a, long long int b) {
	pair<long long int,long long int>answer(1,0);
	if(b==0)return answer;
	if (b % 2) {
		answer=a;
	}
	auto x=solve(a,b/2);
	x=mul(x,x);
	answer=mul(answer,x);

	return answer;
}
int main() {
	int N,K;cin>>N>>K;
	vector<int>v(N);
	for(int i=0;i<N;++i)cin>>v[i];
	sort(v.begin(),v.end());
	long long int answer=1;
	int rest=-1;
	for (int i = N - 1; i >= 0; --i) {
		auto it=upper_bound(v.begin(),v.end(),K-v[i]);
		int num=it-v.begin();
		if (num >= i) {
			rest=N-2*(N-1-i);
			break;
		}
		num-=(N-1-i);
		if(num<0)num=0;
		answer*=num;
		answer%=static_cast<int>(1e9+7);
	}
	if (rest != -1) {
		rest--;
		while (rest > 0) {
			answer*=rest;
			rest-=2;
		}
	}
	cout<<answer<<endl;
   return 0;
}