Program 21.6: A node of a binary tree

public class treenode {

  double data;

  treenode left;
  treenode right;

  public treenode (double d) {
    data = d;
    left = null;
    right = null;
  }

  public void store (double d) {
    if (d <= data) {
      if (left == null) left = new treenode(d);
      else left.store(d);
    }
    else {
       if (right == null) right = new treenode(d);
      else right.store(d);
    }
  }
  
  public void print() {
  
    if (left != null) left.print();
    System.out.println(data);
    if (right != null) right.print();
  
  }
  

}