unit Unit3;

interface

uses
  Classes, StdCtrls, SysUtils;

type
  Summator = class(TThread)
  private
    { Private declarations }
  protected
    procedure Summ;
    procedure Execute; override;
  public
    listbox_input: TListBox;
    listbox_output: TListBox;
    count: integer;
    sum: integer;
  end;

implementation

{ Summator }

procedure Summator.Execute;
begin

  count := 1;

  while count < 100 do
  begin
    Synchronize(Summ);
  end;

end;

procedure Summator.Summ;
var
  i: integer;
begin
  if ((listbox_input.Items.Count div 10) >= count) then
    begin
      sum := 0;
      for i:=0 to 9 do
      begin
        sum := sum + StrToInt(listbox_input.Items[(count-1) * 10 + i]);
      end;
      listbox_output.Items.Add(IntToStr(sum));
      count := count + 1;
  end;
end;

end.