using System;

using System.Collections.Generic;

public class Program

{

    public static List<string> FindStrings(string s, int n) {

        if (n == 0) {

            if (string.IsNullOrEmpty(s)) {

                return new List<string>{ };

            }

            return null; // null means invalid

        }

        for (var i=s.Length-1; i>=0; i--){

            var startOfString = s.Substring(0, i);

            var endOfString = s.Substring(i);

            var list = FindStrings(startOfString, n-1);

            // invalid... gotta continue to next try

            if (list == null) continue;

            // oops, we didn't find the correct number of substrings...

            if (list.Count != n-1) continue;

            // make sure there are no matches so far

            if (list.Contains(endOfString)) continue;

            // bingo!

            list.Add(endOfString);

            return list;

        }

        return null; // null means invalid

    }

    public static void Print(List<string> strs){

        if (strs == null) {

            Console.WriteLine("No set possible");

            return;

        }

        foreach(var str in strs){

            Console.WriteLine(str); 

        }

    }

    public static void Main()

    {

        Print(FindStrings("aababa", 4));

    }

}