import java.util.HashSet; import java.util.Scanner; import java.util.stream.IntStream; public class Main{ static IntStream REPS(int v){return IntStream.range(0,v);} static IntStream REPS(int l,int r){return IntStream.rangeClosed(l,r);} static IntStream INS(int n) {return REPS(n).map(i->getInt());} static Scanner s=new Scanner(System.in); static int getInt(){return Integer.parseInt(s.next());} public static void main(String[]$){ int n=getInt(); int sq=(int)Math.sqrt(n)+1; HashSetr=new HashSet<>(); for(int i=1;i