#include<bits/stdc++.h>
#define ll long long
#define fo(i,a,b) for(ll (i)=(a);(i)<=(b);(i)++)
#define fd(i,a,b) for(ll (i)=(a);(i)>=(b);(i)--)
#define eb emplace_back
using namespace std;
const int N=1e6+10;
int n,k;
int a[N],tmp[N];
vector<int> e[N<<1];
void solve()
{
	cin>>n>>k;
	fo(i,1,n){
		cin>>a[i],a[i]+=1e6;
		e[a[i]].eb(i);
	} 
	ll ans=0;
	fo(x,0,2e6){
		if(e[x].size())
		{
			ans=max(ans,(ll)e[x].size());
			if(x-k<0 || x-k>2e6) continue;
			
			int i=0,j=0,cnt=0;
			while(i<e[x].size() || j<e[x-k].size())
			{
				if(i<e[x].size() && j<e[x-k].size())
				{
					if(e[x][i]<e[x-k][j]) tmp[++cnt]=-1,i++;
					else tmp[++cnt]=1,j++;
				}
				else if(i<e[x].size()){
					tmp[++cnt]=-1,i++;
				}
				else {
					tmp[++cnt]=1,j++;
				}
			}
			ll sum=0,mi=0;
			fo(i,1,cnt){
				sum+=tmp[i];
				ans=max(ans,(ll)e[x].size()+sum-mi);
				mi=min(mi,sum);
			}
		}
	} 
	cout<<ans;
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	int T=1;
//	cin>>T;
	while(T--) solve();
	return 0;
}