#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, d; cin>>n>>d;
vector<int> a(n + 1);
vector<pii> all;
for (int i = 1; i <= n; i++){
cin>>a[i];
all.pb({a[i], i});
}
sort(all.begin(), all.end());
int i = 0, m = 1;
while (i < n){
int j = i;
while (j < n && all[i].ff == all[j].ff){
a[all[j].ss] = m;
j++;
}
m++;
i = j;
}
vector<vector<int>> dp(n + 1, vector<int>(m + 1));
for (int i = 1; i <= n; i++){
dp[i][a[i]] = 1;
for (int j = max(1, i - d); j < i; j++){
dp[i][a[i]] = max({dp[i][a[i]], dp[j][a[i] - 1] + 1, dp[j][a[i]]});
}
for (int x = a[i] + 1; x <= m; x++){
dp[i][x] = dp[i][x - 1];
for (int j = max(1, i - d); j < i; j++){
dp[i][x] = max(dp[i][x], dp[j][x]);
}
}
}
cout<<dp[n][m]<<"\n";
}
