#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>
#include <set>
#define PB push_back
using namespace std;
const int N = 3e5 + 500;
const int OFF = (1 << 19);
const int INF = 0x3f3f3f3f;
int n, d, A[N], sm[N];
vector < int > saz, rv[N];
set < int > S;
int T[2 * OFF], dp[N], sol;
void update(int i, int x){
T[OFF + i] = max(T[OFF + i], x);
for(i = (i + OFF) / 2 ; i ; i /= 2)
T[i] = max(T[2 * i], T[2 * i + 1]);
}
int query(int i, int a, int b, int lo, int hi){
if(lo <= a && b <= hi) return T[i];
if(a > hi || b < lo) return 0;
return max(query(2 * i, a, (a + b) / 2, lo, hi), query(2 * i + 1, (a + b) / 2 + 1, b, lo, hi));
}
inline void remove(int l, int r){
for(auto it = S.lower_bound(l);it != S.end() && *it <= r;it = S.erase(it));
}
int main(){
scanf("%d%d", &n, &d);
for(int i = 0;i < n;i++){
scanf("%d", A + i);
saz.PB(A[i]); S.insert(i);
}
sort(saz.begin(), saz.end());
saz.erase(unique(saz.begin(), saz.end()), saz.end());
for(int i = 0;i < n;i++){
A[i] = lower_bound(saz.begin(), saz.end(), A[i]) - saz.begin();
rv[A[i]].PB(i);
}
for(int i = 0;i < n;i++){
for(int j : rv[i])
remove(j - d + 1, j);
for(int j : rv[i]){
sm[j] = ((int)S.size() == 0 || *S.begin() > j ? 0 : *(--S.lower_bound(j)));
}
}
for(int i = 0;i < n;i++){
reverse(rv[i].begin(), rv[i].end());
for(int j : rv[i]){
dp[j] = query(1, 0, OFF - 1, sm[j], j) + 1;
update(j, dp[j]); sol = max(sol, dp[j]);
}
}
printf("%d\n", sol);
return 0;
}
