如何在c++中添加延迟

#include <iostream>
#include <unistd.h>

int main() {
    std::cout << "Before delay" << std::endl;
    sleep(1); // 暂停1秒钟
    std::cout << "After delay" << std::endl;
    return 0;
}

#include <iostream>
#include <chrono>
#include <thread>

int main() {
    std::cout << "Before delay" << std::endl;
    std::this_thread::sleep_for(std::chrono::seconds(1)); // 暂停1秒钟
    std::cout << "After delay" << std::endl;
    return 0;
}

#include <iostream>
#include <ctime>

int main() {
    std::cout << "Before delay" << std::endl;
    clock_t start_time = clock();
    while ((clock() - start_time) / CLOCKS_PER_SEC < 1) {} // 暂停1秒钟
    std::cout << "After delay" << std::endl;
    return 0;
}