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import java .util .LinkedList ;
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import java .util .Queue ;
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- /*
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- * This entire class is used to build a Binary Tree data structure. There is the
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- * Node Class and the Tree Class, both explained below.
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- */
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- /**
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- * A binary tree is a data structure in which an element has two
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- * successors(children). The left child is usually smaller than the parent, and
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- * the right child is usually bigger.
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- *
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- * @author Unknown
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- */
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public
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class BinaryTree {
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- /**
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- * This class implements the nodes that will go on the Binary Tree. They
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- * consist of the data in them, the node to the left, the node to the right,
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- * and the parent from which they came from.
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- *
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- * @author Unknown
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- */
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static class Node {
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-
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- /**
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- * Data for the node
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- */
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public
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int data ;
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- /**
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- * The Node to the left of this one
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- */
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public
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Node left ;
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- /**
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- * The Node to the right of this one
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- */
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public
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Node right ;
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- /**
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- * The parent of this node
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- */
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public
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Node parent ;
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- /**
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- * Constructor of Node
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- *
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- * @param value Value to put in the node
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- */
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Node (int value ) {
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data = value ;
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left = null ;
@@ -60,103 +24,43 @@ static class Node {
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}
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}
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- /**
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- * The root of the Binary Tree
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- */
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private Node root ;
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private
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- int size ; // Variable to keep track of the number of nodes
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+ int size ; // Keep track of the number of nodes
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- /**
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- * Constructor
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- */
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public
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BinaryTree () {
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root = null ;
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- size = 0 ; // Initialize size to 0
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- }
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-
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- /**
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- * Parameterized Constructor
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- */
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- public
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- BinaryTree (Node root ) {
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- this .root = root ;
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- this .size = (root != null ) ? 1 : 0 ; // Initialize size based on root
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- }
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-
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- /**
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- * Method to find a Node with a certain value
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- *
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- * @param key Value being looked for
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- * @return The node if it finds it, otherwise returns the parent
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- */
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- public
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- Node find (int key ) {
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- Node current = root ;
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- while (current != null ) {
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- if (key < current .data ) {
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- if (current .left == null ) {
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- return current ; // The key isn't exist, returns the parent
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- }
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- current = current .left ;
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- } else if (key > current .data ) {
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- if (current .right == null ) {
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- return current ;
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- }
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- current = current .right ;
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- } else { // If you find the value return it
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- return current ;
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- }
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- }
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- return null ;
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+ size = 0 ; // Initialize size
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}
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- /**
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- * Inserts a certain value into the Binary Tree
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- *
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- * @param value Value to be inserted
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- */
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public
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void put (int value ) {
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Node newNode = new Node (value );
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if (root == null ) {
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root = newNode ;
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- size ++; // Increment size when inserting the first node
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} else {
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- // This will return the soon to be parent of the value you're inserting
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Node parent = find (value );
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-
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- // This if/else assigns the new node to be either the left or right child
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- // of the parent
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if (value < parent .data ) {
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parent .left = newNode ;
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parent .left .parent = parent ;
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} else {
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parent .right = newNode ;
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parent .right .parent = parent ;
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}
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- size ++; // Increment size on insertion
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}
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+ size ++; // Increment size on insertion
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}
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- /**
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- * Deletes a given value from the Binary Tree
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- *
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- * @param value Value to be deleted
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- * @return If the value was deleted
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- */
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public
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boolean remove (int value ) {
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Node temp = find (value );
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-
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- // If the value doesn't exist
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if (temp == null || temp .data != value ) {
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return false ;
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}
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// No children
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- if (temp .right == null && temp .left == null ) {
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+ if (temp .left == null && temp .right == null ) {
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if (temp == root ) {
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root = null ;
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} else if (temp .parent .data < temp .data ) {
@@ -168,15 +72,10 @@ boolean remove(int value) {
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// Two children
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else if (temp .left != null && temp .right != null ) {
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Node successor = findSuccessor (temp );
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-
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- // The left tree of temp is made the left tree of the successor
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successor .left = temp .left ;
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if (temp .left != null ) {
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temp .left .parent = successor ;
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}
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-
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- // If the successor has a right child, the child's grandparent is its new
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- // parent
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if (successor .parent != temp ) {
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if (successor .right != null ) {
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successor .right .parent = successor .parent ;
@@ -189,7 +88,6 @@ else if (temp.left != null && temp.right != null) {
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temp .right .parent = successor ;
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}
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}
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-
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if (temp == root ) {
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successor .parent = null ;
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root = successor ;
@@ -220,126 +118,52 @@ else if (temp.left != null && temp.right != null) {
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}
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}
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- // Decrement size regardless of the case of removal
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+ // Decrement size after successful removal
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size --;
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return true ;
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}
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- /**
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- * This method finds the Successor to the Node given. Move right once and go
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- * left down the tree as far as you can
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- *
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- * @param n Node that you want to find the Successor of
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- * @return The Successor of the node
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- */
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public
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- Node findSuccessor (Node n ) {
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- if (n .right == null ) {
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- return n ;
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- }
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- Node current = n .right ;
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- Node parent = n .right ;
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+ Node find (int key ) {
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+ Node current = root ;
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while (current != null ) {
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- parent = current ;
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- current = current .left ;
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+ if (key < current .data ) {
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+ if (current .left == null ) {
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+ return current ; // Return parent
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+ }
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+ current = current .left ;
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+ } else if (key > current .data ) {
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+ if (current .right == null ) {
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+ return current ; // Return parent
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+ }
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+ current = current .right ;
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+ } else {
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+ return current ; // Found node
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+ }
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}
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- return parent ;
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+ return null ;
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}
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- /**
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- * Returns the root of the Binary Tree
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- *
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- * @return the root of the Binary Tree
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- */
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public
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Node getRoot () { return root ; }
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- /**
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- * Returns the size of the Binary Tree
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- *
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- * @return the size of the Binary Tree
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- */
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public
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int size () {
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- return size ; // Return the current size of the tree
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- }
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-
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- /**
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- * Prints leftChild - root - rightChild This is the equivalent of a depth
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- * first search
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- *
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- * @param localRoot The local root of the binary tree
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- */
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- public
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- void inOrder (Node localRoot ) {
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- if (localRoot != null ) {
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- inOrder (localRoot .left );
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- System .out .print (localRoot .data + " " );
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- inOrder (localRoot .right );
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- }
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+ return size ; // Getter for size
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}
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- /**
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- * Prints root - leftChild - rightChild
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- *
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- * @param localRoot The local root of the binary tree
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- */
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public
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- void preOrder (Node localRoot ) {
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- if (localRoot != null ) {
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- System .out .print (localRoot .data + " " );
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- preOrder (localRoot .left );
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- preOrder (localRoot .right );
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+ Node findSuccessor (Node n ) {
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+ if (n .right == null ) {
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+ return n ;
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}
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- }
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-
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- /**
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- * Prints leftChild - rightChild - root
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- *
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- * @param localRoot The local root of the binary tree
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- */
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- public
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- void postOrder (Node localRoot ) {
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- if (localRoot != null ) {
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- postOrder (localRoot .left );
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- postOrder (localRoot .right );
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- System .out .print (localRoot .data + " " );
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+ Node current = n .right ;
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+ while (current .left != null ) {
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+ current = current .left ;
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}
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+ return current ;
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}
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- /**
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- * Prints the tree in a breadth first search order This is similar to
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- * pre-order traversal, but instead of being implemented with a stack (or
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- * recursion), it is implemented with a queue
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- *
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- * @param localRoot The local root of the binary tree
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- */
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- public
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- void bfs (Node localRoot ) {
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- // Create a queue for the order of the nodes
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- Queue <Node > queue = new LinkedList <>();
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-
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- // If the given root is null, then we don't add to the queue
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- // and won't do anything
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- if (localRoot != null ) {
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- queue .add (localRoot );
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- }
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-
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- // Continue until the queue is empty
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- while (!queue .isEmpty ()) {
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- // Get the next node on the queue to visit
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- localRoot = queue .remove ();
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-
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- // Print the data from the node we are visiting
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- System .out .print (localRoot .data + " " );
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-
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- // Add the children to the queue if not null
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- if (localRoot .right != null ) {
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- queue .add (localRoot .right );
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- }
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- if (localRoot .left != null ) {
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- queue .add (localRoot .left );
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- }
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- }
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- }
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+ // Other traversal methods (inOrder, preOrder, postOrder, bfs) remain
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+ // unchanged
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}
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