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

int main()
{
    std::string message = "Hello, world!";
    for(auto c : message)
    {
        std::cout << c;
        std::this_thread::sleep_for(std::chrono::milliseconds{100});
    }
    std::cout << std::endl;
}