import java.util.*;
import java.io.*;
import java.lang.String;

class rek1 {

	public static void main (String[] args) {
	
		int x;
		Scanner scan = new Scanner(System.in);
		x = scan.nextInt();
		f1(x);
	}//end main

	static void f1(int n){
		System.out.println(n);
		if (n > 1){
			f1(n-1);
		}//end if
		System.out.println(n);
	}//end rek1
}//end rek