// author: erray
#include <bits/stdc++.h>
#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) void(37)
#define here void(37)
#endif
using namespace std;
const int inf = 0;
struct SegTree {
int n;
vector<int> mx;
SegTree(int _n) : n(_n) {
mx.resize((n << 1), -inf);
}
void modify(int i, int p) {
assert(i >= 0 && i < n);
mx[i += n] = p;
while (i > 1) {
mx[(i >> 1)] = max(mx[i], mx[i ^ 1]);
i >>= 1;
}
}
int get(int l, int r) {
assert(l >= 0 && l <= r && r < n);
l += n;
r += n + 1;
int res = -inf;
while (l < r) {
if (l & 1) {
res = max(res, mx[l]);
++l;
}
if (r & 1) {
--r;
res = max(res, mx[r]);
}
l >>= 1;
r >>= 1;
}
return res;
}
};
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int N, D;
cin >> N >> D;
vector<int> A(N);
for (int i = 0; i < N; ++i) {
cin >> A[i];
}
map<int, vector<int>> pos;
for (int i = 0; i < N; ++i) {
pos[A[i]].push_back(i);
}
set<int> block;
for (int i = 0; i < N; ++i) {
block.insert(i);
}
SegTree st(N);
vector<int> dp(N);
for (auto[foo, a] : pos) {
for (auto i : a) {
auto it = block.lower_bound(i);
while (it != block.begin() && *prev(it) + D >= i) {
block.erase(prev(it));
it = block.lower_bound(i);
}
int lim = (it == block.begin() ? 0 : *prev(it) + 1);
debug(i, block);
dp[i] = st.get(lim, i) + 1;
}
for (auto i : a) {
st.modify(i, dp[i]);
}
}
debug(dp);
cout << st.get(0, N - 1) << '\n';
}
