#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
//using mint = static_modint<998244353>;
//using mint = modint;
using mint = static_modint<1000000007>;
using vm = vector<mint>;
using vvm = vector<vm>;
ostream &operator<<(ostream &o,const mint &m){cout<<m.val();return o;}
using ll = long long;
using vl = vector<ll>;
using vvl = vector<vl>;
using pl = pair<ll,ll>;
using vp = vector<pl>;
#define rep(i,n) for(ll i=0;i<(ll)(n);++i)
#define reps(i,s,n) for(ll i=(s);i<(ll)(n);++i)
#define rep1(i,n) for(ll i=1;i<=(ll)(n);++i)
template<typename T>inline bool chmax(T &a,T b){return a<b?a=b,true:false;}
template<typename T>inline bool chmin(T &a,T b){return a>b?a=b,true:false;}
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define be(v) (v).begin(),(v).end()
const long long INF = 1e18;
#ifdef DEBUG
#include <debug.hpp>
random_device rd;
mt19937 gen(rd());
ll random(ll l,ll h){
	uniform_int_distribution<ll> dist(l,h);
	return dist(gen);
}
#endif

const ll MX=100001;
ll N,X;
vl A;
void input(){
	cin>>N>>X;
	A.assign(N,0);
	rep(n,N)cin>>A.at(n);
}
#ifdef DEBUG
void showall(){
	show(N,X);
}
#endif
ll logic(){
	vl v(MX,0);	
	rep(n,N){
		v.at(A.at(n))++;
	}
	vl w = convolution_ll(v,v);
	#ifdef DEBUG
	rep(i,v.size()){
		if(v.at(i)>0)show(i,v.at(i));
	}
	show("---");
	rep(i,w.size()){
		if(w.at(i)>0)show(i,w.at(i));
	}
	#endif
	ll ans;
	if(X < w.size()) ans = w.at(X);
	else ans = 0;
	return ans;
}
#ifdef DEBUG
ll naive(){
	return 1;
}
#endif
int main(){
	#ifdef DEBUG
	cout << "--- Input ---" << endl;
	#endif
	input();
	#ifdef DEBUG
	showall();
	cout << "--- Logic ---" << endl;
	#endif
	ll ans=logic();
	#ifdef DEBUG
	cout << "--- Answer ---" << endl;
	#endif
	cout<<ans<<endl;
	//while(input())logic();
	#ifdef DEBUG
	//show("naive=",naive());
	#endif
	#ifdef DEBUG
	/*
	rep(q,100){
		N=random(1LL,1000LL);
		showall();
		ll lans=logic(),nans=naive();
		if(lans!=nans){ show(" WA",lans,nans); break; }
		else{ show(" AC",lans,nans); }
	}
	*/
	#endif
	return 0;
}
//cout << fixed << setprecision(9);