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#include <cstdio>
#include <vector>
#define nmax 1025
#define mod 103
#define pb push_back
#define mp make_pair
#define sum first
#define cnt second
using namespace std;
vector<pair<int, int> > kush[mod];
int v[nmax];
int n, l, i, j, solutions;
inline int find_value(int x)
{
int list=x%mod;
vector<pair<int, int> >::iterator it;
for(it=kush[list].begin(); it!=kush[list].end(); ++it)
{
if(it->sum==x) return it->cnt;
}
return 0;
}
void insert_value(int x)
{
int list=x%mod;
vector<pair<int, int> >::iterator it;
for(it=kush[list].begin(); it!=kush[list].end(); ++it)
if(it->sum==x)
{
++it->cnt;
return;
}
kush[list].pb(mp(x, 1));
}
int main()
{
freopen("oite.in", "rt", stdin);
freopen("oite.out", "wt", stdout);
scanf("%d%d", &n, &l);
for(i=1; i<=n; ++i)
scanf("%d", &v[i]);
for(i=1; i<=n; ++i)
{
for(j=i+1; j<=n; ++j)
{
if(v[i]+v[j]>l) continue;
solutions+=find_value(l-v[i]-v[j]);
}
for(j=1; j<i; ++j)
{
if(v[i]+v[j]>l) continue;
insert_value(v[i]+v[j]);
}
}
printf("%d\n", solutions);
}