2_1

program Project2;
{$APPTYPE CONSOLE}
uses
   System.SysUtils;
type
   TArray = array of Integer;
const
   EnterError = 'Error! N should be natutal number from 28 to 31';
   FileError = 'Error! Check file data';
   InputFileName = 'input.txt';

procedure InputN(var N : Integer);
var
   IsCorrect : Boolean;
   Input : string;
begin
   IsCorrect := False;
   repeat
      try
         Writeln('Enter N - the number of days');
         Readln(Input);
         N := StrToInt(Input);
         if(N < 28) or (N > 31) then
            Writeln(EnterError)
         else
            IsCorrect := True
      except
         on E : EConvertError do
            Writeln(EnterError);
      end;
   until IsCorrect;
end;

procedure InputFromFile(N : Integer; var Days : TArray);
var
   InputFile : TextFile;
   i, LastIndex : Integer;
begin
   if FileExists(InputFileName) then
      try
      AssignFile(InputFile, InputFileName);
      Reset(InputFile);
      SetLength(Days, N);
      LastIndex := N - 1;
      for i := 0 to LastIndex do
         Read(InputFile, Days[i]);

      for i := 0 to LastIndex do
         Write(Days[i], ' ');

      finally
         CloseFile(InputFile);
      end
   else
      Writeln(FileError);
end;

procedure Output(Amount : Integer);
begin
   Writeln('');
   if FileExists(InputFileName) then
      Writeln('There are ', Amount, ' days with < 0 degrees');
end;

function GetAmountOfColdDays(var Days : TArray) : Integer;
var
   Counter, i, LastIndex : Integer;
begin
   Counter := 0;
   LastIndex := High(Days);
   for i := 0 to LastIndex do
      if Days[i] < 0 then
         Inc(Counter);
   GetAmountOfColdDays := Counter;
end;

procedure Main();
var
   N : Integer;
   Days : TArray;
begin
   Writeln('This program can cal how many times temperature was below 0 degrees');
   InputN(N);
   InputFromFile(N, Days);
   Output(GetAmountOfColdDays(Days));
   Readln;
end;

begin
   Main();
end.