// The Binary Tree ADT -- linked list implementation

class BTNode {

   char data;
   BTNode leftChild;
   BTNode rightChild;

   public BTNode () {
   }

   public BTNode (char newData) {
       data = newData;
   }

   public BTNode (char newData, BTNode newLeftChild, BTNode                           newRightChild) {
       data = newData;
       leftChild = newLeftChild;
       rightChild = newRightChild;
   }

   public void setData (char newData) { 
       data = newData;
   }

   public void setLeftChild (BTNode newLeftChild) {
       leftChild = newLeftChild;
   }

   public void setRightChild (BTNode newRightChild) {
       rightChild = newRightChild;
   }

   public char getData () {
       return data;
   }

   public BTNode getLeftChild () {
       return leftChild;
   }
 
   public BTNode getRightChild () {
      return rightChild;
   }
 
   public void displayBTNode () {
      System.out.print (data + "  ");
   }

}

class BTLRADT {

   BTNode root;

   public BTLRADT () {
   }

   public BTNode getRoot () {
      return root;
   }

/* it is assumed that the tree is based on the ordering
   relationship between data in the nodes */

   public void insert (char newData) {
      BTNode newNode = new BTNode ();
      newNode.data = newData;
      if (root == null)
          root = newNode;
      else {
          BTNode temp = root;
          BTNode parent;
          while (true) {
             parent  = temp;
             if (newData < temp.data)  {   //go left 
                temp = temp.leftChild;
                if (temp == null) {
                   parent.leftChild = newNode;
                   return;
                }
             }
             else {                       // go right
                temp = temp.rightChild;
                if (temp == null) {
                   parent.rightChild = newNode;
                   return;
                }
             }
          }
       }
   }

   public void preOrder (BTNode localRoot) {
      if (localRoot != null) {
         localRoot.displayBTNode();
         preOrder(localRoot.leftChild);
         preOrder(localRoot.rightChild);
      }
   }

   public void postOrder (BTNode localRoot) {
      if (localRoot != null) {
         postOrder(localRoot.leftChild);
         postOrder(localRoot.rightChild);
         localRoot.displayBTNode();
      }
   }

   public void inOrder (BTNode localRoot) {
      if (localRoot != null) {
         inOrder(localRoot.leftChild);
         localRoot.displayBTNode();
         inOrder(localRoot.rightChild);
      }
   }

   public void levelOrder (BTNode localRoot) {
      BTNode[] queue = new BTNode[20];
      int front = 0;
      int rear = -1;
      while (localRoot != null) {
          localRoot.displayBTNode();     
          if (localRoot.leftChild != null) {
              rear++;
              queue[rear] = localRoot.leftChild;
          }
          if (localRoot.rightChild != null) {
              rear++;
              queue[rear] = localRoot.rightChild;
          }
          localRoot = queue[front];
          front++;
      }
   }
}

class BTLRex1 {

   public static void main (String[] args) {

      BTLRADT tree = new BTLRADT();

      tree.insert('b');
      tree.insert('i');
      tree.insert('n');
      tree.insert('a');
      tree.insert('r');
      tree.insert('y');
      tree.insert('t');
      tree.insert('r');
      tree.insert('e');
      tree.insert('e');
      tree.insert('e');
      tree.insert('x');
      tree.insert('a');
      tree.insert('m');
      tree.insert('p');
      tree.insert('l');
      tree.insert('e');  

/*
      tree.insert('5');
      tree.insert('3');
      tree.insert('6');
      tree.insert('2');
      tree.insert('4');
*/
      tree.preOrder(tree.getRoot());
      System.out.println ();
      tree.postOrder(tree.getRoot());
      System.out.println ();
      tree.inOrder(tree.getRoot());
      System.out.println ();
      tree.levelOrder(tree.getRoot());
      System.out.println ();
   }
}