#include <fstream>
#include <algorithm>
#include <vector>
using namespace std;
vector<int> a;

bool cmp(int c, int b) {
	return a[c]<a[b] ?1 :0;
}

int main() {
	ifstream fin("scmax.in");
	ofstream fout("scmax.out");
	int n;
	fin >> n;
	a.resize(n);
	vector<int> minlast, parent(n);
	vector<int>::iterator it;
	for (int i=0; i<n; ++i) fin >> a[i];
	for (int i=0; i<n; ++i) {
		it=lower_bound(minlast.begin(),minlast.end(),i,cmp);
		if (it!=minlast.begin()) parent[i]=*((--it)++);
		if (it==minlast.end()) minlast.push_back(i);
		else *it=i;
	}
	vector<int> lis(minlast.size());// longest increasing subsequence
	for (int i=lis.size()-1, last=minlast.back(); i>=0; --i) {
		lis[i]=last;
		last=parent[last];
	}
	fout << minlast.size() << '\n';
	for (it=lis.begin(); it!=lis.end(); ++it)
		fout << a[*it] << ' ';
	return 0;
}