#include<fstream>
#include<iostream>
#include<string>
using namespace std;
#define nmax 100001
long long a[nmax],best[nmax];
long long i,j,n;
long long caut(long long lol,long long f,long long l){
	long long m=(f+l)/2;
	if(f==l-1)
		m++;
	if(lol<=best[m] && lol>best[m-1])
		best[m]=lol;
	else
		if(lol>=best[m])
			caut(lol,m,l);
		else
			caut(lol,f,m);
}

long long ct;
int main(){
	ifstream f("scmax.in");
	ofstream g("scmax.out");
	
	f>>n;
	for(i=1;i<=n;i++){
		f>>a[i];
		best[i]=2000000000;
	}
	best[n+1]=2000000000;
	
	best[0]=-2000000000;
	for(i=1;i<=n;i++){
		
		caut(a[i],0,n);
		
	}
	for(i=1;i<=n;i++){
		if(best[i]==2000000000){
			i=n+1;
		}
		else{
			ct++;
			
		}
	}
	g<<ct<<"\n";
	for(i=1;i<=ct;i++){
		
			
			g<<best[i]<<" ";
		
	}
	
	return 0;
}