#pragma GCC optimize("Ofast,O2,O3,unroll-loops")
#pragma GCC target("avx2")
#include <bits/stdc++.h>
#include <random>
using namespace std;
void debug_out() { cerr << endl; }
template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
cerr << "[" << H << "]";
debug_out(T...);
}
#ifdef dddxxz
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
#define SZ(s) ((int)s.size())
#define all(x) (x).begin(), (x).end()
#define lla(x) (x).rbegin(), (x).rend()
#define bpc(x) __builtin_popcount(x)
#define bpcll(x) __builtin_popcountll(x)
clock_t startTime;
double getCurrentTime() {
return (double) (clock() - startTime) / CLOCKS_PER_SEC;
}
#define MP make_pair
typedef long long ll;
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const double eps = 0.000001;
const int MOD = 1e9 + 7;
const int INF = 1000000101;
const long long LLINF = 1223372000000000555;
const int N = 1e6 + 3e2;
const int M = 1111;
void compress(vector<int> &a){
map<int, int> mp;
for (int &i : a) mp[i] = 0;
int sz = 0;
for (auto &now : mp) now.second = ++sz;
for (int &i : a) i = mp[i];
}
struct Fenwick{
vector<int> f;
Fenwick(int n){
f.assign(n + 5, 0);
}
void add(int x, int y){
while (x < f.size()){
f[x] = max(f[x], y);
x += (-x & x);
}
}
int get(int x){
int res = 0;
while (x > 0){
res = max(res, f[x]);
x -= (-x & x);
}
return res;
}
};
int report(int n, int d, vector<int> a){
if (d == 1){
vector<int> cnt(n, 0);
stack<int> st;
for (int i = 0; i < n; i++){
while (!st.empty() && a[st.top()] < a[i]) st.pop();
int l = (st.empty() ? 0 : st.top() + 1);
cnt[l]++;
if (i + 1 < n) cnt[i + 1]--;
st.push(i);
}
for (int i = 1; i < n; i++) cnt[i] += cnt[i - 1];
int ans = 0;
for (int i = 0; i < n; i++) ans = max(ans, cnt[i]);
return ans;
}
if (d == n){
Fenwick F(n);
int ans = 0;
for (int i = 0; i < n; i++){
int x = F.get(a[i] - 1) + 1;
ans = max(ans, x);
F.add(a[i], x);
}
return ans;
}
vector<vector<int>> dp(n, vector<int>(n + 1, -1e9));
vector<deque<pair<int, int>>> deq(n + 1); // (dp, i)
for (int i = 0; i < n; i++){
dp[i][a[i]] = 1;
for (int val = 1; val <= n; val++){
while (!deq[val].empty() && deq[val].front().second + d < i) deq[val].pop_front();
}
for (int val = 1; val <= n; val++){
if (deq[val].empty()) continue;
if (val < a[i]){
dp[i][a[i]] = max(dp[i][a[i]], deq[val].front().first + 1);
} else {
dp[i][val] = max(dp[i][val], deq[val].front().first);
}
}
for (int val = a[i]; val <= n; val++){
if (dp[i][val] < 1) continue;
while (!deq[val].empty() && deq[val].back().first <= dp[i][val]) deq[val].pop_back();
deq[val].emplace_back(dp[i][val], i);
}
}
int ans = 0;
for (int val = 0; val <= n; val++) ans = max(ans, dp[n - 1][val]);
return ans;
}
void solve(int TC) {
int n, d;
cin >> n >> d;
vector<int> a(n);
for (int &i : a) cin >> i;
compress(a);
cout << report(n, d, a);
}
int main() {
startTime = clock();
ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
#ifdef dddxxz
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
int TC = 1;
// cin >> TC;
for (int test = 1; test <= TC; test++) {
//debug(test);
//cout << "Case #" << test << ": ";
solve(test);
}
#ifdef dddxxz
cerr << endl << "Time: " << int(getCurrentTime() * 1000) << " ms" << endl;
#endif
return 0;
}
