#include<stdio.h>
#include<stdlib.h>
#include<math.h>
struct point
{
	int x;
	short a,b;
	point *y;
};
point *a[1024000],*p;
int bb[100000][4];
int c,l,i,j,o[1099],m,n,max;
int h(int k)
{
	float c;
	c=(sqrt(5)-1)/2;
	return (int)(m*(k*c-(int)(k*c)));
}
void intro(int k)
{
	point *p;
	int q;
	p=new point;
	p->x=k;
	q=h(k);
	if(q>max)max=q;
	p->x=k;
	p->y=a[q];
	p->a=i;
	p->b=j;
	a[q]=p;
}
bool searchh(int a,int b,int c,int d)
{
	int i,j,v[6],k;bool o;
	v[0]=a;v[1]=b;v[2]=c;v[3]=d;
	for(i=0;i<4;i++)for(j=i;j<n;j++){k=v[i];v[i]=v[j];v[j]=k;}
	for(k=0;k<n;k++)
	{
		o=1;
		for(i=0;i<4;i++)if(bb[k][i]==v[i])o=0;
		if(o)return 1;
	}
	return 0;
}
void introo(int a,int b,int c,int d)
{
	int i,j,v[6],k;
	v[0]=a;v[1]=b;v[2]=c;v[3]=d;
	for(i=0;i<4;i++)for(j=i;j<n;j++){k=v[i];v[i]=v[j];v[j]=k;}
	for(i=0;i<4;i++)bb[n][4]=v[i];
	n++;
}
void search(point *u)
{
	int q;
	q=h(l-u->x);
	point *p;
	p=a[q];
	while(p)
	{
		if(p->x==l-u->x)if(!searchh(p->a,p->b,u->a,u->b)){introo(p->a,p->b,u->a,u->b);return ;}
		p=p->y;
	}
}
int main()
{
	freopen("oite.in","r",stdin);
	freopen("oite.out","w",stdout);
	scanf("%d%d",&c,&l);
	m=(c*c)/3;
	for(i=0;i<c;i++)scanf("%d",&o[i]);
	for(i=0;i<102400;i++)a[i]=NULL;
	for(i=0;i<c-1;i++)
		for(j=i+1;j<c;j++)
			intro(o[i]+o[j]);
	for(i=0;i<=max;i++)
	{
		p=a[i];
		while(p)
		{
			search(p);
			p=p->y;
		}
	}
		
	printf("%d\n",n/2);
	return 0;
}