XDU 1284 寻找礼物

#include <cstdio>
#include <iostream>
#include <cstring>
#include <cmath>
#include <string>
#include <algorithm>

using namespace std;

int a[1010];

int Scan()    //输入外挂
{
int res=0,ch,flag=0;
if((ch=getchar())=='-')
flag=1;
else if(ch>='0'&&ch<='9')
res=ch-'0';
while((ch=getchar())>='0'&&ch<='9')
res=res*10+ch-'0';
return flag?-res:res;
}
void Out(int a)    //输出外挂
{
if(a>9)
Out(a/10);
putchar(a%10+'0');
}

int main()
{
int t,n,k;
scanf("%d",&t);
while(t--)
{
int ans=0;
n=Scan();
k=Scan();
//scanf("%d%d",&n,&k);
for(int i=0;i<n;i++)
a[i]=Scan();
//scanf("%d",&a[i]);
sort(a,a+n);
if(k==0){printf("0\n");continue;}
for(int i=0;i<n;i++)
{
for(int j=i+1;j<n;j++)
{
int sum=k-a[i]-a[j];
int cnt=lower_bound(a+j+1,a+n,sum)-a;
ans+=(n-cnt);
}
}
Out(ans);
printf("\n");
}
return 0;
}