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package algs13;
import java.text.DecimalFormat;
import stdlib.*;
public class PlaygroundWithNonStaticNode {
  private Node first;
  class Node { 
    public double item; 
    public Node next; 
    public Node (double item, Node next) { 
      this.item = item; 
      this.next = next; 
    }
  }

  public static void main (String[] args) {
    Trace.showBuiltInObjects(true);
    Trace.run ();
    PlaygroundWithNonStaticNode list1 = PlaygroundWithNonStaticNode.of ("5 11 5 5");
    PlaygroundWithNonStaticNode list2 = PlaygroundWithNonStaticNode.of ("24 35 67");
    Trace.draw();
  } 

  /* A silly method to show list creation */
  public PlaygroundWithNonStaticNode example(int i) {
    Node x1 = new Node (i+10, null);
    Node x2 = new Node (i+20, null);
    Node x3 = new Node (i+30, null);
    Node x4 = new Node (i+40, null);
    PlaygroundWithNonStaticNode result = new PlaygroundWithNonStaticNode ();
    result.first = x1;
    x1.next = x2;
    x2.next = x3;
    x3.next = x4;
    return result;
  }

  /* ToString method to print */
  public String toString () { 
    // Use DecimalFormat #.### rather than String.format 0.3f to leave off trailing zeroes
    DecimalFormat format = new DecimalFormat ("#.###");
    StringBuilder result = new StringBuilder ("[ ");
    for (Node x = first; x != null; x = x.next) {
      result.append (format.format (x.item));
      result.append (" ");
    }
    result.append ("]");
    return result.toString ();
  }

  /* Method to create lists */
  public static PlaygroundWithNonStaticNode of(String s) {
    PlaygroundWithNonStaticNode result = new PlaygroundWithNonStaticNode ();
    if ("".equals (s)) return result;

    Node first = null;
    String[] nums = s.split (" ");
    for (int i = nums.length-1; i >= 0; i--) {
      try { 
        double num = Double.parseDouble (nums[i]); 
        first = result.new Node (num, first);      
      } catch (NumberFormatException e) {
        throw new IllegalArgumentException (String.format ("Bad argument \"%s\": could not parse \"%s\" as a double", s, nums[i]));
      }
    }
    result.first = first;
    return result;
  }

}