#include <bits/stdc++.h>

//DEBUG:    https://github.com/sharkdp/dbg-macro
#ifdef LOCAL
#include "../Lib/dbg-macro-0.5.1/dbg.h"
#else
#define dbg(...) (__VA_ARGS__)
#endif

#define endl '\n'
using namespace std;
typedef long long ll;
typedef long double llf;
const ll MAXN=2e5+10,MOD=998244353,INF=1e9;

ll qpow(ll base,ll exp){ll ans=1;while(exp){if(exp&1)(ans*=base)%=MOD;(base*=base)%=MOD;exp>>=1;}return ans;}
template<class T>ll max_binary_answer(ll l,ll r,T check,bool cmp=true){ll m;while(l<r){m=(l+r+1)/2;if(cmp^!check(m))l=m;else r=m-1;}return l;}
template<class T>ll min_binary_answer(ll l,ll r,T check,bool cmp=true){ll m;while(l<r){m=(l+r)/2;if(cmp^!check(m))r=m;else l=m+1;}return r;}
ll exgcd(ll a,ll b,ll &x,ll &y){ll tmp;return b==0?(x=1,y=0,a):(tmp=exgcd(b,a%b,y,x),y-=(a/b)*x,tmp);}
ll highbit(ll x){for(ll i=1;i<(ll)sizeof(ll)*4;i<<=1)x|=x>>i;return x-(x>>1);}
ll lowbit(ll x){return x&(-x);}
//--------Global declared area--------

//--------Global declared end --------
void solve(int test_num){
	int n,k,tmp,ans=0;
	cin>>n>>k;
	map<int,vector<int>> m;
	vector<int> cnt(2e6+5);
	for(int i=0;i<n;i++){
		cin>>tmp;
		tmp+=1e6;
		m[tmp].push_back(-1);
		m[tmp+k].push_back(1);
		cnt[tmp]++;
		ans=max(ans,cnt[tmp]);
	}
	if(k!=0){
		for(auto [x,a]:m){
			int sum=0,c=cnt[x];
			for(int i=0;i<(int)a.size();i++){
				if(sum>0){
					sum+=a[i];
				}else{
					sum=a[i];
				}
				ans=max(ans,c+sum);
			}
		}
	}
	cout<<ans<<endl;
}

int main(){
#ifdef ACM
	freopen("D:/Code/C or C++/File/input.txt","r",stdin);
	freopen("D:/Code/C or C++/File/output.txt","w",stdout);
	freopen("D:/Code/C or C++/File/error.txt","w",stderr);
#else
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr),std::cout.tie(nullptr);
#endif
	int t=1;
//	cin>>t;
	for(int i=1;i<=t;i++){
		solve(i);
		//cout.flush();
	}
	return 0;
}