#include <cstdio>
#include <vector>

using namespace std;

#define maxn 1024
#define maxp 204729
#define maxp2 254729

FILE *in = fopen("oite.in", "r"), *out = fopen("oite.out", "w");

struct hash
{
    short i, j;
};

int n;
int L;
int a[maxn];
vector<hash> h[maxp];

hash h1[maxp][5];
hash h2[maxp2][5];

void hadd(int p, int q)
{
    int t = (a[p] + a[q]) % maxp;

    hash tt;
    tt.i = p;
    tt.j = q;

    h[t].push_back(tt);
}

int hget(int p, int q)
{
    int v = (L - (a[p] + a[q]));
    if ( v < 0 )
        return 0;

    int s = 0;
    int t = v % maxp;

    for ( vector<hash>::iterator i = h[t].begin(); i != h[t].end(); ++i )
        if ( i->i > q && a[i->i] + a[i->j] == v )
            ++s;

    return s;
}

int main()
{
    fscanf(in, "%d %d", &n, &L);

    for ( int i = 0; i < n; ++i )
        fscanf(in, "%d", &a[i]);

    for ( int i = 0; i < n; ++i )
        for ( int j = i+1; j < n; ++j )
            hadd(i, j);

    int cnt = 0;
    for ( int i = 0; i < n; ++i )
        for ( int j = i+1; j < n; ++j )
            cnt += hget(i, j);


    fprintf(out, "%d\n", cnt);

	return 0;
}