#include<iostream>
#include<fstream>
using namespace std;
int a[10000],b[10000];
int main ()
{ int n,i,k=1,max,max1;
  ifstream fin("subsir2.in");
  ofstream fout("subsir2.out");
  fin>>n;
  for(i=1;i<=n;i++)
  {
	  fin>>a[i];
  }
  max=a[1];
  max1=1;
  b[max1]=a[1];
  while(max!=100000)
  {
	  max++;
	  for(i=2;i<=n;i++)
	  {
		  if((a[i]==max)&&(i>max1))
		  {
			  max1=i;
			  k++;
			  b[k]=a[i];
		  }
	  }
  }
  fout<<k<<endl;
  for(i=1;i<=k;i++)
  {
	  fout<<b[i]<<" ";
  }
  fin.close();
  fout.close();
  return 0;
}