Моля, за малко помощ...

Не мога да хвана,някое изключение..Ето и кода:

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

namespace _03.Increasing_Crisis
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = int.Parse(Console.ReadLine());
            var output = new List<int>();

            for (int i = 0; i < n; i++)
            {
                var input = Console.ReadLine().Split(' ').Select(int.Parse).ToList();
                var rightMostElement = 0;
                var position = 0;
                var isBreak = false;
                if (output.Count==0)
                {
                    for (int j = 0; j <input.Count ; j++)
                    {
                        output.Add(input[j]);
                    }
                }
                else
                {
                   for (int k = 0; k < output.Count; k++)
                   {
                        if (input[0] > output[k])
                        {
                            rightMostElement = output[k];
                            position = output.IndexOf(rightMostElement);
                        }
                        else if (input[0]==output[k])
                        {
                            position++;
                        }
                   }
                    if (input[0] >= output[0])
                    {
                        output.InsertRange(position + 1, input);
                    }
                   
                }
                var breakElement = 0;
                var breakPosition = 0;
                for (int j = 1; j < output.Count; j++)
                {
                    if (output[j] < output[j-1])
                    {
                        breakElement = output[j];
                        breakPosition = output.LastIndexOf(breakElement);
                        isBreak = true;
                        break;
                    }
                }
                if (isBreak)
                {
                    for (int j = output.Count-1; j >=breakPosition; j--)
                    {
                        output.RemoveAt(j);
                    }
                }
            }
            Console.WriteLine(string.Join(" ",output));
        }
    }
}