#include<stdio.h>
#include<stdlib.h>
#include<math.h>
struct point 
{
	int x;
	short a,b;
	point *y;
};
point *a[10000000],*t;
int c,i,l,m,j,o[1025],max,n;
int h(int k)
{
	/*float c;
	c=(sqrt(5)+1)/2;
	return (int)(m*((k*c)-(int)(k*c)));*/
	return k%399525;
}
void insert(int k)
{
	point *p;
	int q;
	q=h(k);
	if(q>max)max=q;
	p=new point;
	p->x=k;
	p->a=i;
	p->b=j;
	p->y=a[q];
	a[q]=p;
}
void search(point *p)
{
	int q;
	if(l-p->x<0)return;
	q=h(l-p->x);
	point *u;
	u=a[q];
	while(u)
	{
		if(u->x==l-p->x)
			if((u->a!=p->a)&&(u->a!=p->b)&&(u->b!=p->a)&&(u->b!=p->b))
				n++;
		u=u->y;
	}
}
int main()
{
	freopen("oite.in","r",stdin);
	freopen("oite.out","w",stdout);
	scanf("%d%d",&c,&l);
	for(i=0;i<c;i++)scanf("%d",&o[i]);
	m=c/3;
	for(i=0;i<c-1;i++)
		for(j=i+1;j<c;j++) insert(o[i]+o[j]);
	for(i=0;i<=max;i++)
	{
		t=a[i];
		while(t)
		{
			search(t);
			t=t->y;
		}
	}
	printf("%d\n",n/6);
}