#include <bits/stdc++.h>
#define long long long
using namespace std;
struct Seg {
int n;
vector<int> t;
Seg(int _n): n(_n), t(4*n+4, 0) {}
void upd(int p, int v, int i, int l, int r) {
if(l==r) { t[i]=v; return; }
int m=(l+r)>>1;
if(p<=m) upd(p,v,2*i,l,m);
else upd(p,v,2*i+1,m+1,r);
t[i]=max(t[2*i],t[2*i+1]);
}
int query(int L, int R, int i, int l, int r) {
if(R<l||r<L) return 0;
if(L<=l&&r<=R) return t[i];
int m=(l+r)>>1;
return max(query(L,R,2*i,l,m), query(L,R,2*i+1,m+1,r));
}
};
void init(){
#define task "main"
if(fopen(task".INP","r")){
freopen(task".INP","r",stdin);
freopen(task".OUT","w",stdout);
}
ios::sync_with_stdio(false);
cin.tie(nullptr);
}
int main(){
init();
int n, d;
cin >> n >> d;
vector<long> a(n);
for(int i=0;i<n;i++) cin >> a[i];
vector<long> v = a;
sort(v.begin(), v.end());
v.erase(unique(v.begin(), v.end()), v.end());
int M = v.size();
vector<int> c(n);
for(int i=0;i<n;i++){
c[i] = lower_bound(v.begin(), v.end(), a[i]) - v.begin();
}
Seg st(M);
vector<multiset<int>> ms(M);
vector<int> dp(n);
int res = 0;
for(int i=0;i<n;i++){
if(i-d-1 >= 0){
int u = c[i-d-1];
auto it = ms[u].find(dp[i-d-1]);
ms[u].erase(it);
int mv = ms[u].empty() ? 0 : *ms[u].rbegin();
st.upd(u, mv, 1, 0, M-1);
}
int u = c[i];
int best = u>0 ? st.query(0, u-1, 1, 0, M-1) : 0;
dp[i] = best + 1;
ms[u].insert(dp[i]);
st.upd(u, *ms[u].rbegin(), 1, 0, M-1);
res = max(res, dp[i]);
}
cout << res << "\n";
return 0;
}
