Delphi的并行计算

有如下循环体：

hits:=;
for I:= to NumberOfIterations- do
begin
      {perform some calculations dependent on random number generation to determine a value x}
      if x> then hits:=hits+;
end;{For Loop}
FailureProbability:=hits/NumberOfIterations;

如果迭代次数非常大，如何用并行方法完成？答案如下：

program loop;

{$APPTYPE CONSOLE}

const
    NumberOfIterations = ;

type
    TCalcThread = class(TThread)
    private
        FIdx: Integer;
        FHits: Cardinal;
    protected
        procedure Execute; override;
    public
        constructor Create(Idx: Integer); reintroduce;
        property Hits: Cardinal read FHits;
    end;

constructor TCalcThread.Create(Idx: Integer);
begin
    FIdx := Idx;
    FHits := ;
    inherited Create(False);
end;

procedure TCalcThread.Execute;
var
    i, x, start, finish: Integer;
begin
    start := (NumberOfIterations div ) * FIdx;
    finish := start + (NumberOfIterations div ) - ;

    for i := start to finish do begin
        //do your random calculations here
        if x >  then
            Inc(FHits);
    end;
end;

var
    thrarr: array[..] of TCalcThread;
    hndarr: array[..] of THandle;
    i: Integer;
    FailureProbability: Extended;

begin
    for i :=  to  do begin
        thrarr[i] := TCalcThread.Create(i);
        hndarr[i] := thrarr[i].Handle;
    end;

    WaitForMultipleObjects(, @hndarr, True, INFINITE);

    FailureProbability := Extended(thrarr[].Hits + thrarr[].Hits + thrarr[].Hits + thrarr[].Hits) / NumberOfIterations;

    for i :=  to  do
        thrarr[i].Free;
end.