M.rar_圆周率_蒙特卡洛 并行_蒙特卡洛并行

#include <windows.h> #include <process.h> #include <iostream> #include <fstream> #include <cstdlib> #include <ctime> #include <time.h> using namespace std; //------------------------------------------------------ unsigned int n1; //总的计算次数 unsigned int thread_count=2; //线程的个数 unsigned int n2; //总的成功点数 HANDLE mutex; //互斥变量 //----------------------------------------------------- bool judge_n(double x,double y)//判断是否落在圆弧内 { if(x*x+y*y<=1) return true; return false; } //------------------------------------------------------ DWORD WINAPI GetPi(LPVOID parma) { unsigned int i=0; unsigned int n = 0; double x=0,y=0; for(;i<100000000/thread_count;i++) { x=(double)rand()/RAND_MAX;//获得随机数 y=(double)rand()/RAND_MAX;//获得随机数 if(judge_n(x,y)) n2++; n1++; } WaitForSingleObject(mutex,INFINITE); ReleaseMutex(mutex); double Pi=4*(double)n2/(double)n1; printf("π=%f\n",Pi); HANDLE hSemaphore = OpenSemaphore(SEMAPHORE_ALL_ACCESS,TRUE,L"MySemaphore"); ReleaseSemaphore(hSemaphore,1,NULL); return 0; } //------------------------------------------------------------------- void main() { HANDLE * thread; double start,finish; start=(double)clock()/CLOCKS_PER_SEC;//记录运行前的系统时间 Sleep(1000); //睡眠10s thread = new HANDLE[thread_count]; mutex=CreateMutex(NULL,FALSE,L"MyMutex"); HANDLE Finish = CreateSemaphore(NULL,0,1,L"MySemaphoer"); printf("线程计算结果：\n"); for(unsigned int i=0;i<thread_count;i++) thread[i]=CreateThread(NULL,0,GetPi,NULL,0,0); WaitForMultipleObjects(thread_count,thread,TRUE,INFINITE); cout<<endl<<"π="<<4.0*(double)n2/(double)n1<<endl; finish = (double)clock()/CLK_TCK;//记录运行后的系统时间 delete []thread; cout<<"time=" << finish-start <<"s" << endl;//显示程序运行的时间 }