CriticalBreakpoint

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

namespace CriticalBreakpoint
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            List<string> lines = new List<string>();

            long absoluteCriticalRatio = 0;

            string input = Console.ReadLine();

            int count = 0;
            while (input != "Break it.")
            {
                string[] nums = input.Split(' ');
                long num1 = long.Parse(nums[0]);
                long num2 = long.Parse(nums[1]);
                long num3 = long.Parse(nums[2]);
                long num4 = long.Parse(nums[3]);

                lines.Add(input);

                long currentCriticalRatio = Math.Abs((num4 + num3) - (num2 + num1));
                if (absoluteCriticalRatio == 0 && currentCriticalRatio != 0)
                {
                    absoluteCriticalRatio = currentCriticalRatio;
                }
                if (currentCriticalRatio != 0 && currentCriticalRatio != absoluteCriticalRatio)
                {
                    Console.WriteLine("Critical breakpoint does not exist.");
                    return;
                }
                input = Console.ReadLine();
                count++;
            }

            BigInteger criticalBreakPoint = BigInteger.Pow(absoluteCriticalRatio, count) % count;

            foreach (var line in lines)
            {
                Console.WriteLine("Line: [{0}]", string.Join(", ",line.Split(' ')));
            }
            Console.WriteLine("Critical Breakpoint: {0}",criticalBreakPoint);
        }
    }
}