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java_QfG2OA.java

import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.Date;

public class GetPeriod
{
  public static void main(String[] args)
  {
    Date date = new Date(); // Initializes to now.
    Calendar calendar = GregorianCalendar.getInstance();
    calendar.setTime(date);
    int hour = calendar.get(Calendar.HOUR_OF_DAY); // Hour in 24h format
    int minute = calendar.get(Calendar.MINUTE); // Minute of the hour

    int period = hour*60 + minute/30*30; // Integer division rounds down to nearest 30
    
    System.out.print(period);
  }
}