求素数的高效算法（BCB）

//--------------------------------------------------------------------------- #include <vcl.h> #include <math.h> #pragma hdrstop #include "Main.h" //--------------------------------------------------------------------------- #pragma package(smart_init) #pragma link "CGAUGES" #pragma resource "*.dfm" TFormMain *FormMain; //--------------------------------------------------------------------------- __fastcall TFormMain::TFormMain(TComponent* Owner) : TForm(Owner) { } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActTestExecute(TObject *Sender) { ShowMessage("test"); } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActionStartExecute(TObject *Sender) { ListBox->Clear(); ListBox->Items->Append("2"); m_CurrentValue=3; this->Timer->Enabled=true; } //--------------------------------------------------------------------------- bool TFormMain::Pass(int value) { int MaxCircle=floor(sqrt(value)); bool result=true; int index=0; int i=2; while (i<=MaxCircle) { //进度 CGauge->MaxValue=MaxCircle; CGauge->Progress=i; Application->ProcessMessages(); //判断 if (value%i==0) { result=false; //break; } //修正 index++; i=StrToInt(this->ListBox->Items->Strings[index]); }; return(result); } void __fastcall TFormMain::TimerTimer(TObject *Sender) { if(Timer->Tag==0) { Timer->Tag=1; if (Pass(m_CurrentValue)) { this->ListBox->Items->Append(IntToStr(m_CurrentValue)); }; this->Caption=IntToStr(m_CurrentValue); m_CurrentValue+=2; Timer->Tag=0; }; } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActionStartUpdate(TObject *Sender) { this->ActionStart->Enabled=!(this->Timer->Enabled); } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActionStopUpdate(TObject *Sender) { this->ActionStop->Enabled=this->Timer->Enabled; } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActionStopExecute(TObject *Sender) { this->Timer->Enabled=false; this->ActionContinue->Tag=1; } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActionContinueExecute(TObject *Sender) { this->Timer->Enabled=true; } //--------------------------------------------------------------------------- void __fastcall TFormMain::ActionContinueUpdate(TObject *Sender) { this->ActionContinue->Enabled=(!(this->Timer->Enabled))&&(ActionContinue->Tag>0); } //--------------------------------------------------------------------------- void __fastcall TFormMain::FormCreate(TObject *Sender) { this->DoubleBuffered=true; } //---------------------------------------------------------------------------