text: #include <time.h>
  #include <stdio.h>
  #include <string.h>
  
  int main(int argc, char** argv)
  {
      time_t now = time(nullptr);
  
      if (argc == 2 && !strcmp(argv[1], "-u")) {
          printf("%u\n", now);
          return 0;
      }
  
      auto* tm = localtime(&now);
      printf("%4u-%02u-%02u %02u:%02u:%02u\n",
          tm->tm_year + 1900,
          tm->tm_mon + 1,
          tm->tm_mday,
          tm->tm_hour,
          tm->tm_min,
          tm->tm_sec);
      return 0;
  }
  
  