#include<bits/stdc++.h>
using namespace std;
void speed()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
}
const int MAXN = 3e5 + 10;
struct Node
{
int lon, pref, suff, len;
Node()
{
lon = pref = suff = len = 0;
}
};
Node tree[4 * MAXN];
Node unite(Node lf, Node rf)
{
if (lf.len == 0)
return rf;
if (rf.len == 0)
return lf;
Node mf;
mf.lon = max(lf.lon, rf.lon);
mf.lon = max(mf.lon, lf.suff + rf.suff);
mf.len = lf.len + rf.len;
mf.pref = lf.pref;
mf.suff = rf.suff;
if (lf.pref == lf.len)
mf.pref = lf.len + rf.pref;
if (rf.suff == rf.len)
mf.suff = rf.len + lf.suff;
return mf;
}
void build_tree(int root, int left, int right)
{
if (left == right)
{
tree[root].lon = 1;
tree[root].pref = tree[root].suff = 1;
tree[root].len = 1;
return;
}
int mid = (left + right) / 2;
build_tree(root * 2, left, mid);
build_tree(root * 2 + 1, mid + 1, right);
tree[root] = unite(tree[root * 2], tree[root * 2 + 1]);
}
void toggle(int root, int left, int right, int pivot)
{
if (left == right)
{
tree[root].lon = 0;
tree[root].pref = tree[root].suff = 0;
tree[root].len = 1;
return;
}
int mid = (left + right) / 2;
if (pivot <= mid)
toggle(root * 2, left, mid, pivot);
else
toggle(root * 2 + 1, mid + 1, right, pivot);
tree[root] = unite(tree[root * 2], tree[root * 2 + 1]);
}
Node query(int root, int left, int right, int qleft, int qright)
{
if (left > qright || right < qleft)
return Node();
if (left >= qleft && right <= qright)
return tree[root];
int mid = (left + right) / 2;
return unite(query(root * 2, left, mid, qleft, qright),
query(root * 2 + 1, mid + 1, right, qleft, qright));
}
int n, a[MAXN], d, dp[MAXN];
pair < int, int > val[MAXN];
int to[MAXN];
void solve()
{
cin >> n >> d;
for (int i = 1; i <= n; i ++)
{
cin >> a[i];
val[i] = {a[i], -i};
}
sort(val + 1, val + n + 1);
build_tree(1, 1, n);
for (int i = 1; i <= n; i ++)
{
int id = - val[i].second;
toggle(1, 1, n, id);
int l = id - 1, r = n + 1;
while(l + 1 < r)
{
//cout << "here " << l << " : " << r << endl;
int m = (l + r) / 2;
Node cur = query(1, 1, n, id, m);
//cout << "lon " << cur.lon << endl;
if (cur.lon >= d)
r = m;
else
l = m;
}
//cout << id << " : " << l + 1 << endl;
to[id] = l + 1;
if (to[id] > n)
to[id] = n;
}
int res = 0;
for (int i = 1; i <= n; i ++)
{
dp[i] = max(dp[i], 1);
int ls = i;
for (int j = i + 1; j <= to[i]; j ++)
{
if (j - ls > d)
break;
if (a[j] > a[i])
{
//cout << i << " : " << j << endl;
dp[j] = max(dp[j], dp[i] + 1);
}
else
{
if (j == n)
res = max(res, dp[i]);
ls = j;
}
}
}
res = max(res, dp[n]);
//assert(s <= res);
cout << res << endl;
}
int main()
{
solve();
return 0;
}
