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#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream fin("oite.in");
ofstream fout("oite.out");
#define ll long long
#define MOD 6013
#define x first
#define y second
#define mp make_pair
vector < pair< pair<int,int>, pair<int,int> > > Hash[MOD];
vector < pair< pair<int,int>,int> > SumHash[MOD];
ll L,S=0;
int n,v[2024],ok=0,nr=0;
void Read()
{
fin>>n>>L;
for(int i=1;i<=n;i++)
fin>>v[i];
}
void Push_Hash(int i, int j, int k, int m)
{
int s[5],cnt=4;
ok=0;
s[1]=i;s[2]=j;s[3]=k;s[4]=m;
sort(s+1,s+1+cnt);
int l=(i+j+k+m)%MOD;
for(unsigned ct=0;ct<Hash[l].size();ct++)
{
int a=Hash[l][ct].x.x;
int b=Hash[l][ct].x.y;
int c=Hash[l][ct].y.x;
int d=Hash[l][ct].y.y;
if(a==s[1] && b==s[2] && c==s[3] && d==s[4])
{
ok=1;
break;
}
}
if(!ok)
Hash[l].push_back(mp(mp(s[1],s[2]),mp(s[3],s[4])));
}
void Push_Sum(int i, int j)
{
S=v[i]+v[j];
int l=S%MOD;
SumHash[l].push_back(mp(mp(i,j),S));
}
void FirstHash()
{
for(int i=1;i<=n-1;i++)
{
for(int j=i+1;j<=n;j++)
Push_Sum(i,j);
}
}
void FindOptim(int sum, int i, int j)
{
int l=sum%MOD;
for(unsigned ct=0;ct<SumHash[l].size();ct++)
{
int a=SumHash[l][ct].x.x;
int b=SumHash[l][ct].x.y;
int c=SumHash[l][ct].y;
if(c==sum)
{
if(i!=a && i!=b && j!=a && j!=b)
{
ok=0;
Push_Hash(i,j,a,b);
if(!ok)
nr++;
}
}
}
}
void SecondHash()
{
for(int i=1;i<=n-1;i++)
{
for(int j=i+1;j<=n;j++)
{
int S=v[i]+v[j];
int Find=L-S;
FindOptim(Find,i,j);
}
}
}
int main()
{
Read();
FirstHash();
SecondHash();
fout<<nr<<'\n';
}