Recursion

Recursive calls go onto the Call Stack and are popped off when the base case is reached.

Code before recusive call: before recursive stack, while going through Code after recursive call: after recursive stack, while backtracking

See Also

Binary Search Tree

A recursive structure, therefore use recursion. When recursing on a tree, need to handle 3 cases, where the order might change

1. Handle curr node
2. Handle left Subtree
3. Handle right Subtree

Example: Print tree in Preorder Traversal

def preOrder():
	preOrderH(root)
def preOrderH(Node curr):
	if curr == null:
		return
	print(curr.data)
	preOrderH(curr.left)
	preOrderH(curr.right)