using System;
using System.Collections;
using System.IO;
using System.Text;
using System.Text.RegularExpressions;

namespace ua.org.uoi
{
	public enum CheckResult 
	{
		NotChecked, 
		OK, 
		WrongAnswer, 
		BadFile, 
		NoFile, 
		Timeout, 
		RTE, 
		HasOutput, 
		CheckerError, 
		CompileError, 
		PresentationError,
		CheckerProblem
	};

	public class Checker
	{

		private double Dist(double x, double y)
		{
			return Math.Sqrt(x * x + y * y);
		}

		/// <summary>
		/// Check problem DIVIDE
		/// </summary>
		/// <param name="dat">input file</param>
		/// <param name="eta">etalon file</param>
		/// <param name="sol">solution file</param>
		/// <returns>Result of check</returns>
		public CheckResult CheckDivide(byte[] dat, byte[] eta, byte[] sol)
		{	
			double EPS_COINCIDE = 1e-4;
			double EPS_DIST = 1e-2;
			string strEta, strSol;
			bool bad_presentation = false;

			try
			{
				System.IO.StreamReader inpStream = new StreamReader(new System.IO.MemoryStream(sol));
				strSol = inpStream.ReadToEnd();
			}
			catch
			{
				return CheckResult.BadFile;
			}

			try
			{
				System.IO.StreamReader inpStream = new StreamReader(new System.IO.MemoryStream(eta));
				strEta = inpStream.ReadToEnd();
			}
			catch
			{
				return CheckResult.CheckerProblem;
			}

		{
			int spaces = 0;
			for (int i = 0; i < strSol.Length; ++i)
				if (strSol[i] == ' ')
					spaces++;
			if (spaces != 3)
				bad_presentation = true;

			if (!strSol.EndsWith("\r\n"))
				bad_presentation = true;

			if (strSol.IndexOf("\r\n") != strSol.LastIndexOf("\r\n"))
				bad_presentation = true;

			strSol = strSol.Replace("\r\n", " ");
			while (strSol.IndexOf("  ") >= 0)
				strSol = strSol.Replace("  ", " ");
		}

		{
			while (strEta.IndexOf("  ") >= 0)
				strEta = strEta.Replace("  ", " ");
			strEta = strEta.Trim();
		}

			double ex1, ey1, ex2, ey2;
			double x1=0, y1=0, x2=0, y2=0;

			try
			{
				string [] str = strSol.Trim().Split(new char [] {' '});

				int cur = 0;
				for (int i = 0; i < str.Length; ++i)
					if (str[i].Trim().Length == 0)
						return CheckResult.WrongAnswer;
					else
					{
						try
						{
							double el = System.Convert.ToDouble(str[i]);

							if (cur == 0)
								x1 = el;
							else if (cur == 1)
								y1 = el;
							else if (cur ==2 )
								x2 = el;
							else if (cur == 3)
								y2 = el;
							else
								return CheckResult.WrongAnswer;

							cur++;
						}
						catch
						{
							return CheckResult.WrongAnswer;
						}
					}
			}
			catch
			{
				return CheckResult.WrongAnswer;
			}

			try
			{
				int i1, i2, i3;
				i1 = strEta.IndexOf(' ');
				i3 = strEta.LastIndexOf(' ');
				for (i2 = i1+1; strEta[i2] != ' '; ++i2);

				ex1 = System.Convert.ToDouble(strEta.Substring(0, i1));
				ey1 = System.Convert.ToDouble(strEta.Substring(i1, i2-i1));
				ex2 = System.Convert.ToDouble(strEta.Substring(i2, i3-i2));
				ey2 = System.Convert.ToDouble(strEta.Substring(i3));
			}
			catch
			{
				return CheckResult.CheckerProblem;
			}

			double a, b, c, d;
			a = ey1 - ey2;
			b = ex2 - ex1;
			c = ex1 * ey2 - ex2 * ey1;

			// normalizing
			d = Dist(a, b);
			a /= d;
			b /= d;
			c /= d;

			// check if given point coincide
			if (Dist(x1 - x2, y1 - y2) < EPS_COINCIDE)
				return CheckResult.WrongAnswer;

			if (Math.Abs(a * x1 + b * y1 + c) < EPS_DIST && Math.Abs(a * x2 + b * y2 + c) < EPS_DIST)
			{
				// answer seems to be ok, points do not coincide
				// check for presentation error
				if (bad_presentation)
					return CheckResult.PresentationError;
				else
					return CheckResult.OK;
			}

			return CheckResult.WrongAnswer;
		}

	}
}