Damm algorithm: Difference between revisions

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=={{header|Ada}}==

<lang Ada>with Ada.Text_IO;

procedure Damm_Algorithm is

function Damm (Input : in String) return Boolean

is

subtype Digit is Character range '0' .. '9';

Table : constant array (Digit, Digit) of Digit :=

(('0', '3', '1', '7', '5', '9', '8', '6', '4', '2'),

('7', '0', '9', '2', '1', '5', '4', '8', '6', '3'),

('4', '2', '0', '6', '8', '7', '1', '3', '5', '9'),

('1', '7', '5', '0', '9', '8', '3', '4', '2', '6'),

('6', '1', '2', '3', '0', '4', '5', '9', '7', '8'),

('3', '6', '7', '4', '2', '0', '9', '5', '8', '1'),

('5', '8', '6', '9', '7', '2', '0', '1', '3', '4'),

('8', '9', '4', '5', '3', '6', '2', '0', '1', '7'),

('9', '4', '3', '8', '6', '1', '7', '2', '0', '5'),

('2', '5', '8', '1', '4', '3', '6', '7', '9', '0'));

Intern : Digit := '0';

begin

for D of Input loop

Intern := Table (Intern, D);

end loop;

return Intern = '0';

end Damm;

procedure Put_Damm (Input : in String) is

use Ada.Text_IO;

begin

Put_Line ("Damm of " & Input & " validates as " & Damm (Input)'Image);

end Put_Damm;

begin

Put_Damm ("5724");

Put_Damm ("5727");

Put_Damm ("112946");

Put_Damm ("112949");

end Damm_Algorithm;</lang>

{{out}}

<pre>Damm of 5724 validates as TRUE

Damm of 5727 validates as FALSE

Damm of 112946 validates as TRUE

Damm of 112949 validates as FALSE