using System;

public class Program

{

    public static void Main()

    {

        int i,n,j;

        double t;

        n=Convert.ToInt32(Console.ReadLine());

        double [] a=new double[n];

        for(i=0;i<n;i++)

        {

         a[i]=Convert.ToDouble(Console.ReadLine()); 

        }

        for(i=0;i<n-1;i++)

        {

            for(j=0;j<=n-2-i;j++)

            {

                if(a[j]>a[j+1])

                   {

                       t=a[j+1];

                       a[j+1]=a[j];

                      a[j]=t;

                }

            }

        }

        for(i=0;i<n;i++)

        {

            Console.Write("{0}",a[i]);

        }

​

    }

}