using System;

public class buklewhilefinal

{

    public static void Main()

    {

        Console.WriteLine("introduzca n");

        string t;

        t=Console.ReadLine();

        int n = int.Parse(t);

        int i =n;

        int x = 1;

        while ( i>=1){

        Console.Write(i);

        i = i -x;

        x = x + 1;

        }

    }

}