4

with Uppgiftb; use Uppgiftb;
with Ada.Text_IO; use Ada.Text_IO;


procedure Uppgifta is
Date, Next, Prev : Date_Type;
begin
   loop
      begin
	 Get(Date);
	 Put(Date);
	 Next := Next_Date(Date);
	 Put(Next);
	 Prev := Previous_Date(Date);
	 Put(Prev);
	 exit;
      exception
	 when Year_Error =>
	    Put_Line("Year must be 0 or higher");
	    Skip_Line;
	 when Month_Error =>
	    Put_Line("Month must be between 1 and 12");
	    Skip_Line;
	 when Day_Error =>
	    Put_Line("Day must be between 1 and the amount of days in month");
	 when others =>
	    Put_Line("Error does not compute");	    Skip_Line;
      end;
   end loop;
end Uppgifta;



package body Uppgiftb is


   procedure Get(Date : out Date_Type) is
      C : Character;

   begin
      Get(Date.Year);
      if Date.Year < 0 then
	 raise Year_Error;
      end if;
      Get(C);
      Get(Date.Month);
      if Date.Month <= 0 or Date.Month > 12 then
	 raise Month_Error;
      end if;
      Get(C);
      Get(Date.Day);
      if Date.Month = 2 and Date.Day > 28 then
	 raise Day_Error;
      elsif Date.Day <= 0 or Date.Day > 31 then
	 raise Day_Error;
      elsif Date.Month = 4 or Date.Month = 6 or Date.Month = 9 or Date.Month = 11 then
	 if Date.Day > 30 then
	    raise Day_Error;
	 end if;

      end if;



   end Get;


   procedure Put(Date : in Date_Type) is

   begin
      Put(Date.Year);
      Put("-");
      if Date.Month < 10 then
	 Put("0");
      end if;
      Put(Date.Month, Width => 0);
      Put("-");
      if Date.Day < 10 then
	 Put("0");
      end if;
      Put(Date.Day, Width => 0);


   end Put;


   procedure Next_Date(OG : in  Date_Type; Date : out Date_Type) is
   begin
      Date := OG;
      if Date.Month = 2 then
	 if Date.Day = 28 then
	    Date.Day := 1;
	    Date.Month := 3;
	 else
	    Date.Day := Date.Day + 1;
	 end if;

      elsif Date.Month = 4 or Date.Month = 6 or Date.Month = 9 or Date.Month = 11 then
	 if Date.Day = 30 then
	    Date.Day := 1;
	    Date.Month := Date.Month + 1;
	 else
	    Date.Day := Date.Day +1;
	 end if;
      else
	 if Date.Day = 31 then
	    Date.Day := 1;
	    Date.Month := Date.Month + 1;
	 else
	    Date.Day := Date.Day + 1;
	 end if;
	 if Date.Month = 13 then
	    Date.Month := 1;
	    Date.Year := Date.Year +1;
	 end if;
	 end if;


   end Next_Date;
    procedure Previous_Date(OG : in  Date_Type; Date : out Date_Type) is

    begin
       Date := OG;
      if Date.Month = 3 then
	 if Date.Day = 1 then
	    Date.Day := 28;
	    Date.Month := 2;
	 else
	    Date.Day := Date.Day - 1;
	 end if;

      elsif Date.Month = 5 or Date.Month = 7 or Date.Month = 10 or Date.Month = 12 then
	 if Date.Day = 1 then
	    Date.Day := 30;
	    Date.Month := Date.Month - 1;
	 else
	    Date.Day := Date.Day - 1;
	 end if;
      else
	 if Date.Day = 1 then
	    Date.Day := 31;
	    Date.Month := Date.Month - 1;
	 else
	    Date.Day := Date.Day - 1;
	 end if;
	 if Date.Month = 0 then
	    Date.Month := 12;
	    Date.Year := Date.Year - 1;
	 end if;
      end if;

   end Previous_Date;
   function Next_Date(Date : in Date_Type) return Date_Type is
   Nxtdate : Date_Type;
   begin
      Next_Date(Date,Nxtdate);
      return Nxtdate;
   end Next_Date;
   function Previous_Date(Date : in  Date_Type) return Date_Type is
      Predate : Date_Type;
   begin
      Previous_Date(Date,Predate);
      return Predate;
   end Previous_Date;

   function "<"(Left, Right : in Date_Type) return Boolean is

   begin
      if Left.Year = Right.Year then
	 if Left.Month = Right.Month then
	    if Left.Day < Right.Day then
	       return True;
	    else
	       return False;
	    end if;
	 elsif Left.Month < Right.Month then
	    return True;
	 else
	    return False;

	 end if;
      elsif Left.Year < Right.Year then
	 return True;
      else
	 return False;
      end if;
   end "<";
   function ">"(Left, Right : in Date_Type) return Boolean is
   begin
   return Right < Left;
   end ">";
   function "="(Left, Right : in Date_Type) return Boolean is
   begin
      return not( Left < Right) and not (Left > Right);
   end "=";

end Uppgiftb;

with Ada.Text_IO; use Ada.Text_IO;
with Altpaket; use Altpaket;
with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;


procedure Uppgiftf is



   Date1, Date2 : Date_Type;
   Count : Integer := 0;
   Efter: Boolean;
begin
   Put("Mata in dagens datum: ");
   Get(Date1);
   Put("Mata in ett annat datum: ");
   Get(Date2);
   loop
   if Date2 > Date1 then
      Date1 := Next_Date(Date1);
      Count := Count + 1;
      if Date1 = Date2 then
	 Efter := True;
	 exit;
      end if;
   elsif Date2 < Date1 then
      Date1 := Previous_Date(Date1);
      Count := Count + 1;
      if Date1 = Date2 then
	 Efter := False;
	 exit;
      end if;
      end if;
   end loop;
   Put("Det andra datumet är ");
   Put(Count, Width => 0);
   if efter then
      Put(" dagar efter det första");
   else
      Put(" dagar innan det första");
   end if;


end Uppgiftf;

package body Altpaket is


   procedure Get(Date : out Date_Type) is
      C : Character;

   begin
      Get(Date(1));
      if Date(1) < 0 then
	 raise Year_Error;
      end if;
      Get(C);
      Get(Date(2));
      if Date(2) <= 0 or Date(2) > 12 then
	 raise Month_Error;
      end if;
      Get(C);
      Get(Date(3));
      if Date(2) = 2 and Date(3) > 28 then
	 raise Day_Error;
      elsif Date(3) <= 0 or Date(3) > 31 then
	 raise Day_Error;
      elsif Date(2) = 4 or Date(2) = 6 or Date(2) = 9 or Date(2) = 11 then
	 if Date(3) > 30 then
	    raise Day_Error;
	 end if;

      end if;



   end Get;


   procedure Put(Date : in Date_Type) is

   begin
      Put(Date(1));
      Put("-");
      if Date(2) < 10 then
	 Put("0");
      end if;
      Put(Date(2), Width => 0);
      Put("-");
      if Date(3) < 10 then
	 Put("0");
      end if;
      Put(Date(3), Width => 0);


   end Put;


   procedure Next_Date(OG : in  Date_Type; Date : out Date_Type) is
   begin
      Date := OG;
      if Date(2) = 2 then
	 if Date(3) = 28 then
	    Date(3) := 1;
	    Date(2) := 3;
	 else
	    Date(3) := Date(3) + 1;
	 end if;

      elsif Date(2) = 4 or Date(2) = 6 or Date(2) = 9 or Date(2) = 11 then
	 if Date(3) = 30 then
	    Date(3) := 1;
	    Date(2) := Date(2) + 1;
	 else
	    Date(3) := Date(3) +1;
	 end if;
      else
	 if Date(3) = 31 then
	    Date(3) := 1;
	    Date(2) := Date(2) + 1;
	 else
	    Date(3) := Date(3) + 1;
	 end if;
	 if Date(2) = 13 then
	    Date(2) := 1;
	    Date(1) := Date(1) +1;
	 end if;
	 end if;


   end Next_Date;
    procedure Previous_Date(OG : in  Date_Type; Date : out Date_Type) is

    begin
       Date := OG;
      if Date(2) = 3 then
	 if Date(3) = 1 then
	    Date(3) := 28;
	    Date(2) := 2;
	 else
	    Date(3) := Date(3) - 1;
	 end if;

      elsif Date(2) = 5 or Date(2) = 7 or Date(2) = 10 or Date(2) = 12 then
	 if Date(3) = 1 then
	    Date(3) := 30;
	    Date(2) := Date(2) - 1;
	 else
	    Date(3) := Date(3) - 1;
	 end if;
      else
	 if Date(3) = 1 then
	    Date(3) := 31;
	    Date(2) := Date(2) - 1;
	 else
	    Date(3) := Date(3) - 1;
	 end if;
	 if Date(2) = 0 then
	    Date(2) := 12;
	    Date(1) := Date(1) - 1;
	 end if;
      end if;

   end Previous_Date;
   function Next_Date(Date : in Date_Type) return Date_Type is
   Nxtdate : Date_Type;
   begin
      Next_Date(Date,Nxtdate);
      return Nxtdate;
   end Next_Date;
   function Previous_Date(Date : in  Date_Type) return Date_Type is
      Predate : Date_Type;
   begin
      Previous_Date(Date,Predate);
      return Predate;
   end Previous_Date;

   function "<"(Left, Right : in Date_Type) return Boolean is

   begin
      if Left(1) = Right(1) then
	 if Left(2) = Right(2) then
	    if Left(3) < Right(3) then
	       return True;
	    else
	       return False;
	    end if;
	 elsif Left(2) < Right(2) then
	    return True;
	 else
	    return False;

	 end if;
      elsif Left(1) < Right(1) then
	 return True;
      else
	 return False;
      end if;
   end "<";
   function ">"(Left, Right : in Date_Type) return Boolean is
   begin
   return Right < Left;
   end ">";
   function "="(Left, Right : in Date_Type) return Boolean is
   begin
      return not( Left < Right) and not (Left > Right);
   end "=";

end Altpaket;