#include <iostream>
#include "stdio.h"
#include <set>
using namespace std;
int a[100000], n, m = -200000000, k = 0;


int main() {
	freopen("scmax.in","r",stdin);
        freopen("scmax.out","w",stdout);
	scanf("%d", &n);
	for(int i = 0; i < n;++i)
		scanf("%d",a + i);

	set<int> sol;
	set<int>::iterator itr;

	sol.clear();
	for(int i=0; i<n; i++)
	{
		sol.insert(a[i]); 
		itr = sol.find(a[i]);
		itr++; 
		if(itr!=sol.end()) 
			sol.erase(itr);
	}
	
	printf("%d\n", sol.size());
	for(auto x : sol)
		printf("%d ", x);
	return 0;
}