#include <bits/stdc++.h>
using namespace std;
const int N = 3e5+10;
void compress(vector<int*> &v) {
int prv = -1, cnt = 0;
sort(v.begin(), v.end(), [&](int* a, int* b) {
return *a < *b;
});
for (int i = 0; i < (int)v.size(); ++i) {
cnt += prv < *v[i];
prv = *v[i];
*v[i] = cnt;
}
}
vector<int> ids[N], to_delete[N];
int n, d;
int a[N], on[N], rgh[N], p[N], s[N], dp[N], t[4 * N];
int find_set(int x) {
return p[x] == x ? x : p[x] = find_set(p[x]);
}
void union_sets(int u, int v) {
u = find_set(u);
v = find_set(v);
if (u == v) {
return;
}
if (u > v) {
swap(u, v);
}
p[v] = u;
s[u] += s[v];
}
void update(int l, int r, int x, int v, int pos) {
if (l > x || r < x) {
return;
}
if (l == r) {
t[pos] = v;
} else {
int m = l + r >> 1;
update(l, m, x, v, pos << 1);
update(m+1, r, x, v, pos << 1 | 1);
t[pos] = max(t[pos << 1], t[pos << 1 | 1]);
}
}
void update(int id, int v) {
update(1, n, id, v, 1);
}
int query(int l, int r, int L, int R, int pos) {
if (L > r || l > R) return 0;
if (L <= l && R >= r) {
return t[pos];
}
int m = l + r >> 1;
return max(query(l, m, L, R, pos << 1), query(m + 1, r, L, R, pos << 1 | 1));
}
int query(int l, int r) {
return query(1, n, l, r, 1);
}
multiset<int> m[N];
void del(int id, int v) {
m[id].erase(m[id].find(v));
}
void ins(int id, int v) {
m[id].insert(v);
}
int get(int id) {
if (!m[id].empty()) {
return *m[id].rbegin();
}
return 0;
}
int main() {
cin >> n >> d;
vector<int*> coords(n);
for (int i = 1; i <= n; ++i) {
p[i] = i;
s[i] = 1;
cin >> a[i];
coords[i - 1] = &a[i];
}
compress(coords);
for (int i = n; i >= 1; --i) {
ids[a[i]].push_back(i);
}
set<int> st = {n + 1};
for (int i = n; i >= 1; --i) {
for (int id : ids[i]) {
rgh[id] = min(*st.lower_bound(id) + d - 1, n + 1);
on[id] = 1;
if (on[id + 1] == 1) {
union_sets(id, id + 1);
}
if (on[id - 1] == 1) {
union_sets(id, id - 1);
}
int u = find_set(id);
if (s[u] >= d) {
st.insert(u);
}
}
}
for (int i = 1; i <= n; ++i) {
to_delete[rgh[i]].push_back(i);
}
int best = 0;
for (int i = 1; i <= n; ++i) {
dp[i] = query(1, a[i] - 1) + 1;
ins(a[i], dp[i]);
update(a[i], get(a[i]));
for (int id : to_delete[i]) {
del(a[id], dp[id]);
update(id, get(a[id]));
}
best = max(best, dp[i]);
}
cout << best << endl;
}
