Amazon.com Widgets Fun Code of the Week #1

Fun Code of the Week #1

By Nick at October 06, 2011 11:20
Filed Under: Delphi, Fun Code
unit uIsPalindrome;

interface

function IsPalindrome(const aString: string): Boolean;

implementation

uses
       Spring.Collections
     , {$IF CompilerVersion >= 230}System.{$IFEND}SysUtils
     ;

function CleanString(const aString: string): string;
var
  C: char;
begin
  // Remove all non-alpha chars and make all lower case
  // Spaces don't matter, so let's count only letters
  Result := '';
  for C in LowerCase(aString) do
  begin
    if CharInSet(C, ['a'..'z', 'A'..'Z']) then
    begin
      Result := Result + C;
    end;
  end;
end;

function IsPalindrome(const aString: string): Boolean;
var
  Stack: IStack<Char>;
  C: Char;
  NoSpaces: string;
  Temp: string;
begin
  NoSpaces :=  CleanString(aString);

  Stack := TCollections.CreateStack<Char>;
  for C in NoSpaces do
  begin
    Stack.Push(C);
  end;
  Temp := '';
  repeat
    Temp := Temp + Stack.Pop;
  until Stack.Count = 0;
  Result := Temp = NoSpaces;
end;

end.

Added: I always enjoy posting code like this. Note that it is entitled "Fun Code", not "Highly optimized, perfectly written Code". ;-)

blog comments powered by Disqus

My Book

A Pithy Quote for You

"If we seek merely swollen, slothful ease and ignoble peace, if we shrink from the hard contests where men must win at the hazard of their lives and risk all that they hold dear, then bolder and stronger peoples will pass us by, and win for themselves the domination of the world."    –  Theodore Roosevelt

Amazon Gift Cards

General Disclaimer

The views I express here are entirely my own and not necessarily those of any other rational person or organization.  However, I strongly recommend that you agree with pretty much everything I say because, well, I'm right.  Most of the time. Except when I'm not, in which case, you shouldn't agree with me.