package me.ramswaroop.trees;
import me.ramswaroop.common.BinaryNode;
import me.ramswaroop.common.BinarySearchTree;
import me.ramswaroop.common.LinkedStack;
import me.ramswaroop.common.Stack;
import static java.lang.System.out;
/**
* Created by IntelliJ IDEA.
*
* @author: ramswaroop
* @date: 6/26/15
* @time: 7:31 PM
*/
public class InOrderUsingStack {
/**
* In-order traversal of tree using one stack and without recursion.
*
* @param node
*/
public static <E extends Comparable<E>> void inOrderUsingStack(BinaryNode<E> node) {
if (node == null) return;
Stack<BinaryNode<E>> stack = new LinkedStack<>();
BinaryNode<E> curr = node; // set root node as current node
stack.push(curr); // push current node
while (!stack.isEmpty()) {
while (curr != null) {
curr = curr.left;
if (curr != null) stack.push(curr); // push all left nodes of the current node
}
BinaryNode<E> top = stack.pop();
out.print(top.value); // print top of stack
curr = top.right;
if (curr != null) stack.push(curr); // push right child of top node
}
}
public static void main(String a[]) {
BinarySearchTree<Integer> bst = new BinarySearchTree<>();
bst.put(6);
bst.put(3);
bst.put(5);
bst.put(7);
bst.put(8);
bst.put(9);
inOrderUsingStack(bst.root);
}
}