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#include <fstream>
#include <vector>
#include <algorithm>
#define Hmax 1572869
#define Tmax 1025
using namespace std;
ifstream in("oite.in");
ofstream out("oite.out");
typedef long ll;
struct myType{
ll a, b, s;
};
vector<myType> v[Hmax];
vector<myType>::iterator f;
int N;
ll a[Tmax];
long long L, R = 0;
ll h(ll x){
return x % Hmax;
}
void Find(ll a, ll b, ll x){
ll n = h(x);
for(vector<myType>::iterator i = v[n].begin(); i != v[n].end(); i++){
if ((*i).s == x) R++;
}
}
int main(){
in>>N>>L;
for(int i = 1; i <= N; i++){
in>>a[i];
}
sort(a+1, a+N+1);
for(int i = 1; i <= N; i++){
for(int j = i+1; j <= N; j++){
ll s = L - a[i] - a[j];
if(s >= 0 ){
Find(i, j, s);
}
}
for(int k = 1; k < i; k++){
ll s = a[i] + a[k];
if(s <= L ){
myType y = {i, k, s};
ll x = h(s);
v[x].push_back(y);
}
}
}
out<<R<<'\n';
return 0;
}