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#include<stdio.h>
#include<vector>
#define pb push_back
#define maxn 1030
#define MOD 666013
using namespace std;
int n,S,sol;
int a[maxn];
vector<int> H[MOD];
void read()
{
scanf("%d%d",&n,&S);
for(int i=1;i<=n;i++) scanf("%d",&a[i]);
}
inline int hash_key(int k){
return k%MOD;
}
void insert(int val)
{
int k=hash_key(val);
H[k].pb(val);
}
int search(int val)
{
int k=hash_key(val);
for(unsigned int i=0;i<H[k].size();i++)
if(H[k][i]==val) return 1;
return 0;
}
void solve()
{
for(int i=1;i<n;i++)
{
for(int j=i+1;j<=n;j++)
if(search(S-a[i]-a[j])) sol++;
for(int j=1;j<i;j++) insert(a[i]+a[j]);
}
}
int main()
{
freopen("oite.in","r",stdin);
freopen("oite.out","w",stdout);
read();
solve();
printf("%d",sol);
fclose(stdin);
fclose(stdout);
return 0;
}