Delphi指定大小的随机数生成

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procedure TForm1.Button1Click(Sender: TObject);
var
buff:integer;
begin
buff:=strtoint(Edit1.Text);
Randomize; // <---------没有此句 每次random产生的随机序列相同
label1.Caption:=inttostr(random(buff));
end;

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