#include<cstdio>
#include<vector>
#include<algorithm>
#define pb push_back
#define mp make_pair
#define f first
#define s second
const int mod = 524288;
const int maxn = 1050;
using namespace std;
vector <pair<pair<int,int>,int> > hash[mod];
int i , j , n , l , v[maxn] , sol , cnt , k , sum , ind;

int main()
{
	freopen("oite.in","r",stdin);
	freopen("oite.out","w",stdout);
	
	scanf("%d %d",&n,&l);
	for( i = 1 ; i <= n ; ++i )
		scanf("%d",&v[i]);
	
	sort ( v + 1 , v + n + 1);
	
	for ( i = 1 ; i <= n ; ++i )
		for( j = i + 1 ; j <= n ; ++j )
			hash[(v[i] + v[j]) & ( mod - 1)].pb(mp(mp(i,j),v[i] + v[j]));
	
		
	for ( i = 1 ; i <= n ; ++i )
		for( j = i + 1 ; j <= n ; ++j ) {
			sum = (l - (v[i] + v[j])) ;
			if ( sum < 0 ) continue;
			ind = sum & ( mod - 1);
			cnt = 0;
			for( k = 0 ; k < hash[ind].size() ; ++k )
				if( hash[ind][k].s == sum && j < hash[ind][k].f.f)
					cnt++ ;
			sol += cnt;
		}

//printf("%d\n",sol);
printf("%d\n",sol );
return 0;
}