unit1.~pas

本光盘是《Delphi 7应用教程》一书的配套光盘

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  nc,nh,nch:integer;                     //定义三个整型变量
begin
  for nc:=1 to 20 do                //公鸡的取值范围为1至20
    begin
      for nh:=1 to 33 do //母鸡的取值范围为1至33，for语句嵌套for语句
        begin
          nch:=100-nc-nh;           //小鸡的取值为100减去公鸡和母鸡数
          if ((nc*5+nh*3+nch/3)=100) then //当买鸡的钱等于100时满足要求
            begin
              Edit1.Text:=IntToStr(nc);
              Edit2.Text:=IntToStr(nh);
              Edit3.Text:=IntToStr(nch);
              break;    //找到一种答案即可，因此用Break语句终止所有循环
            end;
        end;
    end;  
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  Edit1.Text:='';                //对三个编辑框清零
  Edit2.Text:='';
  Edit3.Text:='';
end;

end.