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#include<cstdio>
#include<vector>
using namespace std;
const int MOD = 10009;
const int NMAX = 1030;
struct Hash
{
vector<int> H[MOD+2];
void Adauga(int x)
{
int r=x%MOD;
H[r].push_back(x);
}
int Cauta(int x)
{
if(x<0) return 0;
int r=x%MOD,ans=0;
vector<int>::iterator it;
for(it=H[r].begin(); it!=H[r].end(); it++)
if(*it==x) ans++;
return ans;
}
};
int N,Sol;
int A[NMAX],L;
Hash H;
int main()
{
int i,j;
freopen("oite.in","r",stdin);
freopen("oite.out","w",stdout);
scanf("%d%d",&N,&L);
for(i=1; i<=N; i++)
scanf("%d",&A[i]);
for(i=1; i<=N; i++)
{
for(j=i+1; j<=N; j++)
Sol+=H.Cauta(L-A[i]-A[j]);
for(j=1; j<=i-1; j++)
H.Adauga(A[i]+A[j]);
}
printf("%d\n",Sol);
return 0;
}