OpenMP求完数

源代码：

 #include "stdafx.h"  //必须写在首行，因为其前面的include都会被忽略
 #include "omp.h"
 #include <Windows.h>
 #include "time.h"
 #include <iostream>
 #include <set>
 using namespace std;
 
　　//串行方式
 set<int> FinishedNumber(int n)
 {
     set<int> s;
     for (int i = ; i <= n; i++)
     {
         int maxv = (int)(sqrt(double(i)) + );
         int sum = ;
         for (int j = ; j<maxv; j++)
         if (i%j == )
             sum += j + i / j;
         if (sum == i)
             s.insert(i);
     }
     return s;
 }

　　//并行方式
 set<int> FinishedNumber(int n, int p)
 {
     set<int> s;
     omp_set_num_threads(p);
 #pragma omp parallel
 #pragma omp for
     for (int i = ; i <= n; i++)
     {
         int maxv = (int)(sqrt(double(i)) + );
         int sum = ;
         for (int j = ; j<maxv; j++)
         if (i%j == )
             sum += j + i / j;
         if (sum == i)
             s.insert(i);
     }
     return s;
 }

 void Test(int step, int count)
 {
     /*int step=100000;
     int count=5;*/
     for (int i = ; i <= count; i++)
     {
         int n = i*step;
         clock_t start_Serial = clock();

         set<int> result = FinishedNumber(n);
         printf("n=%d以内的所有完数为：\n", n);
         for (set<int>::iterator it = result.begin(); it != result.end(); it++)
         {
             /*cout<<*it<<endl;*/
             printf("%d\n", *it);
         }

         clock_t end_Serial = clock();
         double timeCollapsedSerial = end_Serial - start_Serial;
         printf("n=%d, 串行方式运行耗时：%f\n", n, timeCollapsedSerial);

         int p = ;
         double timeCollapsedParallel = ;
         for (int power = ; power<; power++)
         {
             p = pow(, power);
             clock_t start_Parallel = clock();
             FinishedNumber(n, p);
             clock_t end_Parallel = clock();
             timeCollapsedParallel = end_Parallel - start_Parallel;
             float accelerationRate = timeCollapsedSerial / timeCollapsedParallel;
             printf("n=%d, p=%d, 并行方式运行耗时: %f,加速比: %.3f\n", n, p, timeCollapsedParallel, accelerationRate);
         }

         printf("\n");
     }
 }
 int _tmain(int argc, _TCHAR* argv[])
 {
     int step =  * ;
     int count = ;
     Test(step, count);
     system("pause");
 }

运行结果：