#include<bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
const int maxn=3e5+100;
#define all(v) v.begin(),v.end()
struct Node{
int val;
Node* left,*right;
Node() : left(nullptr),right(nullptr){}
};
void update(Node* node,int l,int r,int ql,int x){
if(l==r){
node->val=max(node->val,x);
return;
}
int mid=(l+r)>>1;
if(ql<=mid){
if(node->left==nullptr) node->left=new Node();
update(node->left,l,mid,ql,x);
}else{
if(node->right==nullptr) node->right=new Node();
update(node->right,mid+1,r,ql,x);
}
int c=0;
if(node->left) c=max(node->left->val,c);
if(node->right) c=max(node->right->val,c);
node->val=c;
}
int query(Node* node,int l,int r,int ql,int qr){
if(ql>qr) return 0;
if(!node) return 0;
if(ql<=l&&r<=qr) return node->val;
int mid=(l+r)/2;
int ans=0;
if(ql<=mid) ans=max(ans,query(node->left,l,mid,ql,qr));
if(qr>mid) ans=max(ans,query(node->right,mid+1,r,ql,qr));
return ans;
}
signed main(){
Node* root=new Node();
int n,d;
cin>>n>>d;
vector<int> v(n);
for(int i=0;i<n;i++){
cin>>v[i];
}
vector<int> c=v;c.insert(c.begin(),-1);sort(all(c));c.erase(unique(all(c)),c.end());
map<int,int> mp;for(int i=0;i<c.size();i++) mp[c[i]]=i;
int ans=0;
for(int i=0;i<n;i++){
int x=query(root,0,c.size()-1,0,mp[v[i]]-1);
x++;
ans=max(ans,x);
update(root,0,c.size()-1,mp[v[i]],x);
}
cout<<ans<<endl;
}
