#include <cstdio>

using namespace std;

const int mod=2000000,prim=103;
int v[1030];
int dsp[mod+1],nr[mod+1];


int hashh(int a)
{
    int x=(1LL*a*prim)%mod;
    while(1)
    {
        if(dsp[x]==a) {nr[x]++;break;}
        if(dsp[x]==0) {dsp[x]=a;nr[x]=1;break;}
        else x++;
        if(x==mod) x=0;
    }
}

int main()
{
    freopen("oite.in","r",stdin);
    freopen("oite.out","w",stdout);
    int c,l,t,a;
    long long sol=0;
    scanf("%d%d",&c,&l);
    for(int i=1;i<=c;i++)
        scanf("%d",&v[i]);
    for(int i=2;i<c;i++)
    {
        for(int j=1;j<i;j++) hashh(v[i]+v[j]);
        for(int j=i+2;j<=c;j++)
        {
            t=l-v[j]-v[i+1];
            if(t>0)
            {
                a=(1LL*t*prim)%mod;
                while(1)
                {
                    if(dsp[a]==0) break;
                    if(dsp[a]==t) {sol+=nr[a];break;}
                    else a++;
                    if(a==mod) a=0;
                }
            }
        }
    }
    printf("%lld",sol);
    return 0;
}