Iterative_In-order_Traversal

Author: Partho Biswas

README.md

@@ -283,6 +283,7 @@ If you have any questions about the solutions you can find here, feel free to co
 |---| ----- | -------- | -------- | -------- |
 |01| [Invert_Binary_Tree](algoexpert.io/questions/Invert_Binary_Tree.md) | [Python](algoexpert.io/python/Invert_Binary_Tree.py)|
 |02| [Max_Path_Sum_In_Binary_Tree](algoexpert.io/questions/Max_Path_Sum_In_Binary_Tree.md) | [Python](algoexpert.io/python/Max_Path_Sum_In_Binary_Tree.py) |
+|03| [Iterative_In-order_Traversal](algoexpert.io/questions/Iterative_In-order_Traversal.md) | [Python](algoexpert.io/python/Iterative_In-order_Traversal.py) |
 
 
 ### Dynamic Programming
@@ -381,6 +382,7 @@ If you have any questions about the solutions you can find here, feel free to co
 |03| [Caesar_Cipher_Encryptor](algoexpert.io/questions/Caesar_Cipher_Encryptor.md) | [Python](algoexpert.io/python/Caesar_Cipher_Encryptor.py)|
 |04| [Longest_Substring_Without_Duplication](algoexpert.io/questions/Longest_Substring_Without_Duplication.md) | [Python](algoexpert.io/python/Longest_Substring_Without_Duplication.py)|
 |05| [Underscorify_Substring](algoexpert.io/questions/Underscorify_Substring.md) | [Python](algoexpert.io/python/Underscorify_Substring.py)|
+|06| [Pattern_Matcher](algoexpert.io/questions/Pattern_Matcher.md) | [Python](algoexpert.io/python/Pattern_Matcher.py)|
 
 
 ### Tries

algoexpert.io/python/Iterative_In-order_Traversal.py

@@ -0,0 +1,25 @@
+
+
+# O(n) time | O(1) space
+def iterativeInOrderTraversal(tree, callback):
+    previousNode = None
+    currentNode = tree
+    while currentNode is not None:
+        if previousNode is None or previousNode == currentNode.parennt:
+            if currentNode.left is not None:
+                nextNode = currentNode.left
+            else:
+                callback(currentNode)
+                nextNode = currentNode.right if currentNode.right is not None else currentNode.parennt
+        elif previousNode == currentNode.left:
+            callback(currentNode)
+            nextNode = currentNode.right if currentNode.right is not None else currentNode.parennt
+        else:
+            nextNode = currentNode.parennt
+        previousNode = currentNode
+        currentNode = nextNode
+
+
+
+
+