计算代码运行时间

• clock()函数
  • clock_t clock(void);
  • typedef long clock_t;
  • #define CLOCKS_PER_SEC  1000 //故每个clock为1ms

     1 #include<iostream>
     2 #include<time.h>
     3 
     4 int main()
     5 {
     6 clock_t start_time=clock();
     7 
     8 {
     9 //被测试代码
    10 }
    11 
    12 clock_t end_time=clock();
    13 cout<< "Running time is: "<<static_cast<double>(end_time-start_time)/CLOCKS_PER_SEC*1000<<"ms"<<endl;//输出运行时间
    14 return 0;
    15 }

• GetTickCount()函数
  • DWORD GetTickCount(void);
  • elapsed time < 49.7days

     1 #include<iostream>
     2 #include<windows.h>
     3 
     4 int main()
     5 {
     6 DWORD start_time=GetTickCount();
     7 {
     8 //此处为被测试代码
     9 }
    10 DWORD end_time=GetTickCount();
    11 cout<<"The run time is:"<<(end_time-start_time)<<"ms!"<<endl;//输出运行时间
    12 return 0;
    13 }