clock()函数在C++中的使用示例有哪些

1. 计算程序运行时间

#include <iostream> #include <ctime>  int main() {     clock_t start, end;     start = clock();          // 执行需要计时的代码          end = clock();     double duration = double(end - start) / CLOCKS_PER_SEC;          std::cout << "程序运行时间：" << duration << "秒" << std::endl;          return 0; } 

2. 计算函数执行时间

#include <iostream> #include <ctime>  void func() {     clock_t start, end;     start = clock();          // 执行需要计时的代码          end = clock();     double duration = double(end - start) / CLOCKS_PER_SEC;          std::cout << "函数执行时间：" << duration << "秒" << std::endl; }  int main() {     func();          return 0; } 

3. 计算两个操作之间的时间间隔

#include <iostream> #include <ctime>  int main() {     clock_t start, end;     start = clock();          // 执行操作1          end = clock();     double duration1 = double(end - start) / CLOCKS_PER_SEC;          start = clock();          // 执行操作2          end = clock();     double duration2 = double(end - start) / CLOCKS_PER_SEC;          std::cout << "操作1执行时间：" << duration1 << "秒" << std::endl;     std::cout << "操作2执行时间：" << duration2 << "秒" << std::endl;          return 0; }