#include<bits/stdc++.h>
#define debug(x) cerr<<#x<<":"<<x<<"\n"
using namespace std;
using ll = long long;
using pii = pair <int,int>;
const int N = 1e6 + 5, MOD = 1e9 + 7;
const int inf = 1 << 30;
int n;
ll k, a[N], g[N], ans;
map <int,vector<ll>> mp;
map<ll,ll> cnt;
void solve()
{
    cin>>n>>k;
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
        mp[a[i]].emplace_back(-1);
        mp[a[i]+k].emplace_back(1);
        cnt[a[i]]++;
    } 
    for(auto [num,v]:mp)
    {
        ll mx = -inf;
        vector <ll> f(v.size(),-inf);
        mx = f[0] = v[0];
        for (int i=1;i<v.size();i++) 
        {
            f[i] = max(v[i],v[i]+f[i-1]);
            mx = max(mx,f[i]);
        }
        ans = std::max(ans, mx + cnt[num]);
    }
    cout<<ans;
}
int main(void)
{
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    int T = 1;
    // cin >> T;
    while(T--) solve();
    return 0;
}