using System;

using System.Linq;

public class Program

{

    class pCodeDto

    {        

    }

​

    public static void Main()

    {

            var pCodes = new pCodeDto[5].ToList();

            var poCodes = new pCodeDto[3].ToList();

​

            var maxCodes = Math.Max(pCodes.Count, poCodes.Count);

            for (var i = maxCodes - 1; i > -1; i--)

            {

                var code = (i < pCodes.Count) ? pCodes.ElementAt(i) : new pCodeDto();

                var poCode = (i < poCodes.Count) ? poCodes.ElementAt(i) : new pCodeDto();

            }

    }

}