Bubble sort

From Lazarus wiki
Jump to navigationJump to search
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

English (en) suomi (fi) français (fr)

Bubble sort is a simple sorting algorithm.

Characteristics

  • Very slow
  • Suitable only for small quantities sorting
  • Fast only when the array is nearly sorted

Unit UBubbleSort

unit UBubbleSort;

interface

type
  // data type
  TItemBubbleSort=integer;

procedure BubbleSort( var a: array of TItemBubbleSort );


implementation

procedure swap( var a, b:TItemBubbleSort );
var
  temp : TItemBubbleSort;
begin
  temp := a;
  a := b;
  b := temp;
end;


procedure BubbleSort( var a: array of TItemBubbleSort );
var
  n, newn, i:integer;
begin
  n := high( a );
  repeat
    newn := 0;
    for i := 1 to n   do
      begin
        if a[ i - 1 ] > a[ i ] then
          begin
            swap( a[ i - 1 ], a[ i ]);
            newn := i ;
          end;
      end ;
    n := newn;
  until n = 0;
end;

end.

Example of usage

uses
  UBubbleSort
  ...

var
  a: array[0..100] of integer; 
begin
  ...
  BubbleSort(a);
  ...

See also