2_4

program Project2;
{$APPTYPE CONSOLE}
uses
   System.SysUtils;
const
   ErrorMessage = 'Error! Incorrect input (N should be natural number from 1 to 2147483647)';
   InputFileName = 'input.txt';
   OutputFileName = 'output.txt';
   FileCompositionError = 'Error! Your file is composed incorrectly';
   ReadFileError = 'Error! Flie contains invalid data';
type
   TDots = array of array [0..2] of Integer;

procedure Calculate(var Dots : TDots);
var
   Counter, i, j, LastIndex : Integer;
   OutputFile : TextFile;

begin
   Counter := 0;
   LastIndex := High(Dots);
   Assign(OutputFile, OutputFileName);
   Rewrite(OutputFile);
   Writeln('Next dots are in 1-st quarter:');
   Writeln(OutputFile, 'Next dots are in 1-st quarter:');
   for i := 0 to LastIndex do
      if (Dots[i][0] >= 0) and (Dots[i][1] >= 0) then
      begin
         Counter := Counter + 1;
         Writeln('(', Dots[i][0], ' , ', Dots[i][1], ') ');
         Writeln(OutputFile, '(', Dots[i][0], ' , ', Dots[i][1], ') ');
      end;
   Writeln(' = ', Counter, ' in genereal');
   Writeln(OutputFile, ' = ', Counter, ' in genereal');
   CloseFile(OutputFile);
end;


procedure ReadAndPrintDots(var Dots : TDots);
var
   Counter, i : Integer;
   IsCorrect : Boolean;
   InputFile : TextFile;
   Name, Input : string;
begin
   i := 0;

   Writeln('Enter file name');
   Readln(Name);
   while not FileExists(Name) do
   begin
      Writeln('No such file. Input file name again');
      Readln(Name);
   end;

   IsCorrect := True;
   try
      AssignFile(InputFile, InputFileName);
      Reset(InputFile);
      while not EoF(InputFile) and IsCorrect do
      begin
         SetLength(Dots, i + 1);
         Read(InputFile, Dots[i][0]);
         if EoLN(InputFile) then
            IsCorrect := False;
         Read(InputFile, Dots[i][1]);
         if not EoLN(InputFile) then
            IsCorrect := False;
         //Write('(', Dots[i][0], ' ', Dots[i][1], '), ');
         Inc(i);
      end;
      if not IsCorrect then
         Writeln(FileCompositionError)
      else
         Calculate(Dots);
   except
      Writeln(ReadFileError);
   end;
   CloseFile(InputFile);
end;

procedure Main();
var
   Dots : TDots;
begin
   Writeln('This program can calculate how many dots are in the 1-st quarter');
   ReadAndPrintDots(Dots);
   Readln;
end;

begin
   Main();
end.