#include <bits/stdc++.h>
#define ar array
//#define int long long
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 1e5 + 5;
struct union_find {
int n;
vector<int> par, size, L, R, mx;
union_find(int _n) : n(_n), par(n+1), size(n+1, 1), L(n+1), R(n+1), mx(n+1, 0) {
for(int i=1; i<=n; i++) par[i] = L[i] = R[i] = i;
}
int find(int u) {
if(u == par[u]) return u;
return par[u] = find(par[u]);
}
void uni(int a, int b) {
a = find(a); b = find(b);
if(a == b) return ;
if(size[a] < size[b]) swap(a, b);
size[a] += size[b];
par[b] = a;
L[a] = min(L[a], L[b]);
R[a] = max(R[a], R[b]);
mx[a] = max(mx[a], mx[b]);
}
void set_dp(int u, int val) {
mx[find(u)] = max(mx[find(u)], val);
}
int get_l(int u) {
return L[find(u)];
}
int get_r(int u) {
return R[find(u)];
}
int get_dp(int u) {
return mx[find(u)];
}
};
struct segment_tree {
int n;
vector<int> tree, lazy;
segment_tree(int _n) : n(_n), tree(4*n), lazy(4*n) {}
void push(int u, int tl, int tr) {
if(!lazy[u]) return ;
tree[u] = max(tree[u], lazy[u]);
if(tl != tr) {
lazy[2*u] = max(lazy[2*u], lazy[u]);
lazy[2*u+1] = max(lazy[2*u+1], lazy[u]);
}
lazy[u] = 0;
}
void update(int u, int tl, int tr, int l, int r, int v) {
push(u, tl, tr);
if(tl > r || l > tr) return ;
if(l <= tl && tr <= r) {
lazy[u] = max(lazy[u], v);
push(u, tl, tr);
return ;
}
int tm = (tl + tr) / 2;
update(2*u, tl, tm, l, r, v);
update(2*u+1, tm+1, tr, l, r, v);
tree[u] = max(tree[2*u], tree[2*u+1]);
}
int query(int u, int tl, int tr, int l, int r) {
if(tl > r || l > tr) return 0;
push(u, tl, tr);
if(l <= tl && tr <= r) return tree[u];
int tm = (tl + tr) / 2;
return max(query(2*u, tl, tm, l, r), query(2*u+1, tm+1, tr, l, r));
}
void update(int l, int r, int v) { update(1, 1, n, l, r, v); }
int query(int l, int r) { return query(1, 1, n, l, r); }
};
signed main() {
int n, d; cin >> n >> d;
vector<int> dp(n+1), a(n+1);
map<int, vector<int> > mp;
for(int i=1; i<=n; i++) {
cin >> a[i];
mp[a[i]].push_back(i);
}
int diff = 0;
union_find dsu(n);
segment_tree sgt(n);
vector<int> act(n+1);
for(auto [val, vec] : mp) {
for(int p : vec) {
dp[p] = 1;
// for(int j=1; j<=n; j++) cout << dp[j] << " ";
// cout << '\n';
int last = p;
for(int j=p-1; j>=1; j--) {
if(last - j > d) break;
if(act[j]) last = j;
if(a[j] != a[p]) dp[p] = max(dp[p], dp[j] + 1);
}
act[p] = 1;
}
}
cout << *max_element(dp.begin(), dp.end()) << '\n';
return 0;
}
