package leto_cvic03;
public class Interval {
public final double low;
public final double high;
   public Interval(double l, double h) {
       low=l;
       high=h;
   }
   public Interval(){
       low=Double.POSITIVE_INFINITY;
       high=Double.NEGATIVE_INFINITY;
   }
   public boolean isEmpty(){
       return low > high;
   }
   public String toString(){
       if(isEmpty())return "interval is empty";
       return "Interval ["+low+", "+high+"]";

   }
  public static Interval prunik(Interval a, Interval b) {
    if (a==null || b==null ) return new Interval();
    return new Interval(
       Math.max(a.low, b.low), // maximum low
       Math.min(a.high, b.high) // minimum high
    );
 }

 public static Interval prunik(Interval[] p) {
    if (p==null || p.length==0 || p[0]==null)
        return new Interval();

    Interval res= new Interval(p[0].low, p[0].high);
    for (int i = 1; i < p.length; i++) {
       res=Interval.prunik(res, p[i]);
    }
    return res;
 }
   public static void main(String[] args){
       Interval it1=new Interval();
       System.out.println(it1.toString());
   }

}
_________________________________
cvic 03C XInterval
_________________________________
package leto_cvic03c;
import leto_cvic03.*;
public class XInterval extends Interval {

   public XInterval(double l, double h) {
       super (l,h);
   }
   public XInterval() {
       super ();
   }
   public String toString(){
       return "X"+super.toString();
   }
   public double getLength(){
       return high-low;
   }
   //pretizeni
   public XInterval[] union(XInterval a , XInterval b){


   }
   public XInterval[] union(XInterval[] pole){}
  /* public static void main(String[] args){
       Interval it1=new Interval(20,30);
       System.out.println(it1.toString());
   }*/

}