輸入年月日，求出是第幾周．

import java.util.Calendar;

class test{
  public static void main(String[] args){
    Calendar cal = Calendar.getInstance();

    int year = Integer.parseInt(args[0]);
    int month = Integer.parseInt(args[1]);
    int day = Integer.parseInt(args[2]);
    cal.set(year, month-1, day);

    System.out.println(cal.get(Calendar.WEEK_OF_MONTH));
    System.out.println(cal.get(Calendar.WEEK_OF_YEAR));
  }
}