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Java - Data Structure (Binary Trees)

Binary Trees are one of the fundamental data storage structures used in programming. They provide advantages that the data structures we've seen so far cannot.

Why use binary tree?Usually, because it combines the advantages of two other structures: an ordered and array and a linked list. You can search a tree quickly, as you can with an ordered array, and you can also insert and deleted items quickly,as you can with a linked list.

The disadvantage of an ordered array: slow insertion and deletion.
Disadvantage of a linked list: slow searching.

What is a Tree: A tree consists of nodes connected by edges.
                   O -- Node
                 /    \  --- Edges
               /        \
             O         O
            /  \

In computers programs, nodes often represent such entities as people, car parts, airline reservations, and so on.
Edges are likely to be represented in a program by references, if the program is written in Java( or by pointers if the program is written in C or C++)
class Node{
int iData;
node leftChild;
node rightChild;
class Tree{
private Node root;
Node find(key)
public Node find(int key){
Node current = root;
while(current.iData != key){
  if(key > current.iData) current = current.leftChild;
  else current = current.rightChild;
if(current == null) return null ; // didn't find it
} // end where
return current;

//Successor is left descendant of Right Child of delNode
node getSuccessor(node delNode){
Node successorParent = delNode;
node successor = delNode;
Node current = delNode.rightChild; // go to right child until no more left children
while(current != null){
successorParenet = successor;
successor = current;
current = current.leftChild ; //go to left child if successor not  right child,
if(successor != delNode.rightChild) {
successorParent.leftchild = successor.rightChild;
successor.rightChild = delNode.rightChild;
 return successor;


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