Enumerate sandwich numbers

Exactly like in the exercise "Sandwich numbers", we define a sandwich number as a natural number $n$ with only two different digits $d$ and $e$ that are repeated in the form $de_1e_2\cdots e_kd$ , with $k \geq 1$ .

Write a program that displays all the sandwich numbers of $X$ digits on the screen.

Input

The input consists of a natural number $X$ , with $3 \leq X \leq 9$ .

Output

A list of sandwich numbers of $X$ digits, one per line. The numbers can be written in any order. You can generate the numbers as you wish, either as integers or character by character.

Problem information

Author: PRO1

Generation: 2026-01-25T21:36:33.218Z