换乐赛第9题#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define db double
#define il inline
#define re register
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define int ll
#define F(i,a,b) for(re int (i)=(a);(i)<=(b);(i)++)
#define DF(i,a,b) for(re int (i)=(a);(i)>=(b);(i)--)
#define G(i,u) for(re int (i)=head[u];(i);(i)=nxt[(i)])
inline ll read(){ll x=0,f=1;char ch=getchar();while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}while(ch>='0'&&ch<='9'){x=(x<<3)+(x<<1)+ch-48;ch=getchar();}return x*f;}
const int N=10010;
int n,k,ans;
int a[N],b[N];
signed main()
{
n=read(),k=read();
F(i,1,n) a[i]=read();
F(i,1,n) b[i]=read();
sort(a+1,a+n+1);
sort(b+1,b+n+1);
b[n+1]=LINF;
F(i,1,n)
{
int r=upper_bound(b+1,b+n+2,k-a[i])-b-1;
int l=lower_bound(b+1,b+n+2,k-a[i])-b;
if(b[l]+a[i]==k&&b[r]+a[i]==k)
{
ans+=r-l+1;
}
}
printf("%lld",ans);
return 0;
}