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#include <cstdio>
#include <vector>
#define CMAX 2955
#define MOD 666013
using namespace std;
vector<long long>h[MOD];
long long c,l;
long long v[CMAX];
void addtohash(long long x)
{
h[x%MOD].push_back(x);
}
long long findit(long long x)
{
long long ct=0;
long long key=(l-x)%MOD;
vector<long long>::iterator it;
for(it=h[key].begin();it!=h[key].end();++it)
{
if(*it==l-x) ++ct;
}
return ct;
}
int main()
{
freopen ("oite.in","r",stdin);
freopen ("oite.out","w",stdout);
scanf("%lld%lld",&c,&l);
long long ct=0;
for(int i=1;i<=c;i++)
{
scanf("%lld",&v[i]);
}
for(int i=1;i<c;i++)
{
for(int j=i+1;j<=c;j++)
{
ct+=findit(v[i]+v[j]);
}
for(int j=1;j<i;j++)
{
addtohash(v[i]+v[j]);
}
}
printf("%lld\n",ct);
}