Re: creating an array

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

"isaac2004" <isaac_2004@yahoo.com> writes:
>>But I still think my solution is much, much better :)
> sorry havent learned that far yet, but i cant seem to get your code
> to work by itself, it throws a error about a loop where the first if
> statement is. oh well it wasnt tested but i would like ot see a
> running program of that if possible.

OK, it took me another minute or two.  Here is the corrected version,
followed by the diff so you can see what I changed.

(in retrospect, "if X not in 1 .. 10" reads better than "if not X in 1
.. 10", don't you think?

-- 
Ludovic Brenta.


-- Caveat student: not compiled or tested; just wrote this in 10 minutes.
-- Caveat student: your teacher probably reads c.l.a, too :)
with Ada.Integer_Text_IO;
with Ada.Text_IO;
procedure Sort_And_Display is
   subtype Digit_Type is Character range '0' .. '9';
   type Occurrences_Type is array (Digit_Type) of Natural;
   Expected_Number_Of_Digits : Positive;
   User_Input : String (1 .. 10);
   Last : Natural;
   Occurrences : Occurrences_Type := (others => 0);
   Bad_Input : exception;
begin
   Ada.Text_IO.Put ("How many digits (1 .. 10)? ");
   Ada.Integer_Text_IO.Get (Expected_Number_Of_Digits);
   Ada.Text_IO.Skip_Line;
   if Expected_Number_Of_Digits not in 1 .. 10 then
      raise Bad_Input;
   end if;
   Ada.Text_IO.Put ("Now type your number consisting of " &
                    Integer'Image (Expected_Number_Of_Digits) &
                    " digits: ");
   Ada.Text_IO.Get_Line (User_Input, Last);
   if Last > Expected_Number_Of_Digits then
      raise Bad_Input;
   end if;

   -- Parse the character string
   for J in 1 .. Last loop
      if User_Input (J) not in Digit_Type then
         raise Bad_Input;
      end if;
      Occurrences (User_Input (J)) := Occurrences (User_Input (J)) + 1;
   end loop;

   -- Now, Occurrences is naturally sorted; just walk over it.
   for K in Occurrences'Range loop
      for L in 1 .. Occurrences (K) loop
         Ada.Text_IO.Put (K);
      end loop;
   end loop;
end Sort_And_Display;



--- /tmp/ediff10085Ca	2006-02-15 22:51:09.000000000 +0100
+++ /tmp/sort_and_display.adb	2006-02-15 22:51:09.000000000 +0100
@@ -1,6 +1,7 @@
 -- Caveat student: not compiled or tested; just wrote this in 10 minutes.
 -- Caveat student: your teacher probably reads c.l.a, too :)
-with Ada.Text_IO.Integer_IO;
+with Ada.Integer_Text_IO;
+with Ada.Text_IO;
 procedure Sort_And_Display is
    subtype Digit_Type is Character range '0' .. '9';
    type Occurrences_Type is array (Digit_Type) of Natural;
@@ -11,13 +12,13 @@
    Bad_Input : exception;
 begin
    Ada.Text_IO.Put ("How many digits (1 .. 10)? ");
-   Ada.Text_IO.Integer_IO.Get (Expected_Number_Of_Digits);
+   Ada.Integer_Text_IO.Get (Expected_Number_Of_Digits);
    Ada.Text_IO.Skip_Line;
-   if not Expected_Number_Of_Digits in 1 .. 10 then
+   if Expected_Number_Of_Digits not in 1 .. 10 then
       raise Bad_Input;
    end if;
    Ada.Text_IO.Put ("Now type your number consisting of " &
-                    Integer'Image (Expected_Number_Of_Digit) &
+                    Integer'Image (Expected_Number_Of_Digits) &
                     " digits: ");
    Ada.Text_IO.Get_Line (User_Input, Last);
    if Last > Expected_Number_Of_Digits then
@@ -26,11 +27,11 @@
 
    -- Parse the character string
    for J in 1 .. Last loop
-      if not User_Input (J) in Digit_Type then
+      if User_Input (J) not in Digit_Type then
          raise Bad_Input;
       end if;
       Occurrences (User_Input (J)) := Occurrences (User_Input (J)) + 1;
-   end if;
+   end loop;
 
    -- Now, Occurrences is naturally sorted; just walk over it.
    for K in Occurrences'Range loop