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#include <stdio.h>
#include <stdlib.h>
#define MOD 666013
#define MAXN 4000000
#define BUF_SIZE 16384
char buf[BUF_SIZE];
long long pbuf=BUF_SIZE;
FILE*fi,*fo;
inline char nextch(){
if(pbuf==BUF_SIZE){
fread(buf, BUF_SIZE, 1, fi);
pbuf=0;
}
return buf[pbuf++];
}
inline long long nextnum(){
long long a=0;
char c=nextch();
while((c<'0' || c>'9') && c!='-')
c=nextch();
long long semn=1;
if(c=='-'){
semn=-1;
c=nextch();
}
while('0'<=c && c<='9'){
a=a*10+c-'0';
c=nextch();
}
return a*semn;
}
class Hash{
public: long long k, next[MAXN+1], lista[MOD];
long long val[MAXN+1];
long long d[MAXN+1];
inline void insert(long long x, long long y){
k++;
val[k]=x;
d[k]=y;
next[k]=lista[x%MOD];
lista[x%MOD]=k;
}
inline void erase(long long x){
long long p=lista[x%MOD];
if(p==0)
return ;
if(val[p]==x){
lista[x%MOD]=next[lista[x%MOD]];
return ;
}
while((next[p]!=0)&&(val[next[p]]!=x))
p=next[p];
if(next[p]!=0)
next[p]=next[next[p]];
}
long long find(long long x){
long long p=lista[x%MOD];
if(p==0)
return -1;
if(val[p]==x)
return p;
while(next[p]!=0 && val[next[p]]!=x)
p=next[p];
if(next[p]!=0)
return p;
return -1;
}
} H1;
long long v[1024];
long long main(){
fi=fopen("oite.in","r");
fo=fopen("oite.out","w");
long long n=nextnum(), l=nextnum();
for(long long i=0;i<n;i++)
v[i]=nextnum();
long long sol=0LL;
for(long long i=0;i<n;i++){
for(long long j=i+1;j<n;j++){
long long rest=l-v[i]-v[j];
if(rest>=0 && H1.find(rest)!=-1)
sol+=1LL*H1.d[H1.find(rest)];
}
for(long long j=0;j<i;j++)
if(H1.find(v[i]+v[j])==-1)
H1.insert(v[i]+v[j], 1);
else
H1.d[H1.find(v[i]+v[j])]++;
}
fprintf(fo,"%lld", sol);
fclose(fi);
fclose(fo);
return 0;
}