#include <cstdio>

using namespace std;

const int mod=2000000,prim=103;
int v[1030];
int dsp[mod+1][2];


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

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