#include <bits/stdc++.h>
#define int long long
using namespace std;
namespace std {
template <typename T> ostream &operator<<(ostream &out, const vector<T> &vec) {
out << "[";
for (int i = 0; i < (int)vec.size(); ++i) {
out << vec[i];
if (i + 1 < (int)vec.size())
out << ", ";
}
return out << "]";
}
} // namespace std
void dbg_out() { cout << endl; }
template <typename Head, typename... Tail> void dbg_out(Head H, Tail... T) {
cout << ' ' << H;
dbg_out(T...);
}
#ifdef DEBUG
#define dbg(...) cout << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#else
#define dbg(...)
#endif
struct UnionFind {
vector<int> id;
vector<int> smallest;
UnionFind() {}
UnionFind(int N) {
id.assign(N, -1);
smallest.resize(N);
iota(smallest.begin(), smallest.end(), 0);
}
int find(int u) {
if (id[u] < 0)
return u;
return id[u] = find(id[u]);
}
bool merge(int u, int v) {
u = find(u), v = find(v);
if (u == v)
return false;
if (id[u] > id[v])
swap(u, v);
id[u] += id[v];
id[v] = u;
smallest[u] = min(smallest[u], smallest[v]);
return true;
}
};
const int INF = 1e18;
signed main(void) {
ios_base::sync_with_stdio(false);
cin.tie(0);
int N, D;
cin >> N >> D;
vector<int> A(N);
for (int &x : A)
cin >> x;
vector<int> order(N);
iota(order.begin(), order.end(), 0);
sort(order.begin(), order.end(), [&](int i, int j) { return A[i] < A[j]; });
set<int> starts;
UnionFind dsu(N);
vector<int> firstBad(N);
int curAdded = N - 1;
for (int i = N - 1; i >= 0; --i) {
int x = A[order[i]];
while (x < A[order[curAdded]]) {
int j = order[curAdded];
if (j and A[j - 1] > x)
dsu.merge(j - 1, j);
if (j + 1 < N and A[j + 1] > x)
dsu.merge(j, j + 1);
int id = dsu.find(j);
if (-dsu.id[id] >= D)
starts.insert(dsu.smallest[id]);
curAdded--;
}
auto it = starts.lower_bound(order[i]);
firstBad[order[i]] = it == starts.end() ? N : min(N, *it + D);
}
dbg(firstBad);
int start = 1;
while (start < N)
start *= 2;
vector<int> seg(2 * start);
auto setPos = [&](int pos, int x) {
pos += start;
seg[pos] = x;
while (pos > 1) {
pos /= 2;
seg[pos] = max(seg[2 * pos], seg[2 * pos + 1]);
}
};
auto query = [&](int deb, int fin) {
int ret = 0;
deb += start, fin += start;
while (deb < fin) {
if (deb % 2)
ret = max(ret, seg[deb++]);
if (fin % 2)
ret = max(ret, seg[--fin]);
deb /= 2;
fin /= 2;
}
return ret;
};
vector<int> pos(N);
for (int i = 0; i < N; ++i)
pos[order[i]] = i;
vector<int> sortedA = A;
sort(sortedA.begin(), sortedA.end());
vector<vector<int>> toDelete(N);
for (int i = 0; i < N; ++i)
if (firstBad[i] < N)
toDelete[firstBad[i]].push_back(i);
for (int i = 0; i < N; ++i) {
for (int j : toDelete[i])
setPos(pos[j], 0);
auto fin =
lower_bound(sortedA.begin(), sortedA.end(), A[i]) - sortedA.begin();
int LIS = query(0, fin) + 1;
dbg(i, fin, LIS);
setPos(pos[i], LIS);
}
cout << query(0, N) << endl;
}
