#include <bits/stdc++.h>

using namespace std;
using i64 = long long;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int n, k;
  cin >> n >> k;

  vector a(n, 0);
  unordered_map<int, int> num;
  for (auto& x : a) {
    cin >> x;
    num[x]++;
  }

  unordered_map<int, int> cnt;
  unordered_map<int, int> mx;
  for (auto& x : a) {
    cnt[x - k] = max(0, cnt[x - k] - 1);
    cnt[x]++;
    mx[x] = max(mx[x], cnt[x]);
  }

  int ans = 0;
  for (auto& x : a) {
    ans = max(ans, mx[x - k] + num[x]);
  }
  cout << ans;

  return 0;
}