#include<cstdio>
#include<vector>
#define MOD 666013
using namespace std;
int v[1025];
vector<pair<int,int> > hash[666013];
int main ()
{freopen ("oite.in","r",stdin);
freopen ("oite.out","w",stdout);
int n,i,j,k,x,l,q,nr;
bool pp;
nr = 0;
scanf("%d%d",&n,&k);
for(i = 1; i <= n; i++)
    scanf("%d",&v[i]);
for(i = 1; i <= n; i++)
    for(j = n; j >= 1; j--)
        if(j > i && v[i] + v[j] <= k)
            {// numar perechile din hash cu care perechea i,j poate juca
            x = k - (v[i] + v[j]);
            q = x % MOD;
            for(l = 0; l < hash[q].size(); l++)
                if(hash[q][l].first == x)
                    nr += hash[q][l].second;
            }
        else if(j < i)
            {// adaug perechea i,j in hash
            x = v[i] + v[j];
            q = x % MOD;
            pp = false;
            for(l = 0; l < hash[q].size(); l++)
                if(hash[q][l].first == x)
                    {hash[q][l].second++;
                    pp = true;
                    l = hash[q].size();
                    }
            if(pp == false)
                hash[q].push_back(make_pair(x, 1));
            }
printf("%d",nr);
return 0;
}