#include <chrono>
#include <iostream>
 
unsigned int millis_since_midnight()
{
    std::chrono::time_point<std::chrono::system_clock> now = std::chrono::system_clock::now();
 
    time_t tnow = std::chrono::system_clock::to_time_t(now);
    tm *date = std::localtime(&tnow);
    date->tm_hour = 0;
    date->tm_min = 0;
    date->tm_sec = 0;
    auto midnight = std::chrono::system_clock::from_time_t(std::mktime(date));
 
    return std::chrono::duration_cast<std::chrono::milliseconds>(now - midnight).count();
}
 
int main()
{
   std::cout << millis_since_midnight();
}