#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
const i64 P = 998244353;
const int N = 1e6 + 5;
int f[N << 2], g[N << 2];
void solve() {
    int n, k, ans = 0;
    cin >> n >> k;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        a[i] += 2 * N;
        f[a[i]]++;
        ans = max(ans, f[a[i]]);
    }
    for (int i = 0; i < n; i++) {
        g[a[i]]--;
        if (g[a[i]] < 0) g[a[i]] = 0;
        g[a[i] + k]++;
        ans = max(ans, f[a[i] + k] + g[a[i] + k]);
    }
    cout << ans << '\n';
}
int main() {
    ios::sync_with_stdio(0); cin.tie(0), cout.tie(0);
    int t = 1; 
    // cin >> t;
    while(t--) solve();
    return 0;
}