SPOJ Problem#2

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace task2
{
    class pn
    {
        static public int[] PrimeNumbers(int m, int n)
        {
            int size=0;
            int[] result = new int[size];
            if (m==1)  {m=2;}
            if (n==1)  {n=2;}
            for (int i = m; i <= n; i++)
            {
                int testprime=0;
                for (int j = 2; j < i; j++)
                {
                    if (i % j == 0)
                    { testprime++; }
                }
                if (testprime == 0)
                {
                    size++;
                    Array.Resize<int>(ref result, size);
                    result[size - 1] = i;
                }
            }
            int LPN = result.Length;
            return result;
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
                 int t = Int32.Parse(Console.ReadLine());
                 int[][] mn=new int[t][];
                 for (int i = 0; i < t; i++)
                 {
                     string line = Console.ReadLine();
                     mn[i] = line.Split(' ').Select(s => { return s == "" ? 0 : Convert.ToInt32(s); }).ToArray();
                 }
                 for (int i = 0; i < t; i++)
                 {
                     if (mn[i][0]==1 && mn[i][1]==1)
                     {
                         Console.WriteLine("");
                         break;
                     }
                     int lenght=pn.PrimeNumbers(mn[i][0], mn[i][1]).Length;
                     int[] PNresult=new int[lenght];
                     Array.Copy(pn.PrimeNumbers(mn[i][0], mn[i][1]), PNresult, lenght);
                     for (int j = 0; j < lenght;j++)
                     {
                         Console.WriteLine("{0}", PNresult[j]);
                     }
                     Console.WriteLine("");
                 }
                 Console.ReadLine();
        }
    }
}