unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1 = class(TForm)
Memo1: TMemo;
Button1: TButton;
Button2: TButton;
Button3: TButton;
Button4: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure Button4Click(Sender: TObject);
procedure FormCreate(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
type
PMyRec = ^MyRec;
MyRec = record
Name: string[8];
Age : Word;
Link: PMyRec;
end;
var
CurrentNode, FirstNode: PMyRec;
{建立鏈表}
procedure TForm1.FormCreate(Sender: TObject);
begin
New(FirstNode);
FirstNode.Name := '李四';
FirstNode.Age := 44;
FirstNode.Link := nil;
CurrentNode := FirstNode;
New(FirstNode);
FirstNode.Name := '張三';
FirstNode.Age := 33;
FirstNode.Link := CurrentNode;
CurrentNode := FirstNode;
New(FirstNode);
FirstNode.Name := '錢二';
FirstNode.Age := 22;
FirstNode.Link := CurrentNode;
CurrentNode := FirstNode;
New(FirstNode);
FirstNode.Name := '趙一';
FirstNode.Age := 11;
FirstNode.Link := CurrentNode;
CurrentNode := FirstNode;
Button1.Caption := '遍歷鏈表';
Button2.Caption := '插入節點';
Button3.Caption := '刪除節點';
Button4.Caption := '刪除鏈表';
Memo1.Align := alLeft;
Memo1.ScrollBars := ssVertical;
end;
{遍歷鏈表節點}
procedure TForm1.Button1Click(Sender: TObject);
begin
Memo1.Clear;
CurrentNode := FirstNode;
while Assigned(CurrentNode) do
begin
Memo1.Lines.Add(CurrentNode.Name + #9 + IntToStr(CurrentNode.Age));
CurrentNode := CurrentNode.Link;
end;
end;
{插入節點}
procedure TForm1.Button2Click(Sender: TObject);
var
NewNode: PMyRec;
begin
{譬如是插入在第二個節點後面}
CurrentNode := FirstNode.Link;
New(NewNode);
NewNode.Name := 'AAA';
NewNode.Age := 100;
{前後連起來}
NewNode.Link := CurrentNode.Link;
CurrentNode.Link := NewNode;
{調用遍歷}
Button1.Click;
end;
{刪除節點}
procedure TForm1.Button3Click(Sender: TObject);
begin
{譬如是刪除第二個節點}
CurrentNode := FirstNode.Link; {讓 CurrentNode 指向第二個節點}
if Assigned(CurrentNode.Link) then {如果 CurrentNode 還有下一個}
begin
FirstNode.Link := CurrentNode.Link; {不能斷了鏈}
Dispose(CurrentNode); {釋放用 New 申請的內存}
end;
Button1.Click;
end;
{銷燬鏈表, 釋放所有節點}
procedure TForm1.Button4Click(Sender: TObject);
begin
CurrentNode := FirstNode; {從鏈頭向下刪除}
while Assigned(FirstNode) do
begin
CurrentNode := FirstNode;
FirstNode := CurrentNode.Link;
Dispose(CurrentNode);
end;
Button1.Click;
end;
end.
單向鏈表的添加、刪除與遍歷
發表評論
所有評論
還沒有人評論,想成為第一個評論的人麼? 請在上方評論欄輸入並且點擊發布.