master-algorithms-py/src/trees/transversal_BST_iteratively.py
2014-08-27 22:34:33 -04:00

92 lines
2.3 KiB
Python

#!/usr/bin/python
__author__ = "Mari Wahl"
__email__ = "marina.w4hl@gmail.com"
from collections import deque
from binary_search_tree import BinarySearchTree, NodeBST
class BSTwithTransversalIterative(BinarySearchTree):
def inorder(self):
current = self.root
nodes, stack = [], []
while stack or current:
if current:
stack.append(current)
current = current.left
else:
current = stack.pop()
nodes.append(current.item) # thats what change
current = current.right
return nodes
def preorder(self):
current = self.root
nodes, stack = [], []
while stack or current:
if current:
nodes.append(current.item) # thats what change
stack.append(current)
current = current.left
else:
current = stack.pop()
current = current.right
return nodes
def preorder2(self):
nodes = []
stack = [self.root]
while stack:
current = stack.pop()
if current:
nodes.append(current.item)
stack.append(current.right)
stack.append(current.left)
return nodes
def BFT(self):
current = self.root
nodes = []
queue = deque()
queue.append(current)
while queue:
current = queue.popleft()
nodes.append(current.item)
if current.left:
queue.append(current.left) # LEFT FIRST!
if current.right:
queue.append(current.right)
return nodes
if __name__ == '__main__':
bst = BSTwithTransversalIterative()
l = [10, 5, 6, 3, 8, 2, 1, 11, 9, 4]
for i in l:
bst.addNode(i)
print "Is 8 a leaf? ", bst.isLeaf(8)
print "Whats the level of node 8? ", bst.getNodeLevel(8)
print "Is node 10 a root? ", bst.isRoot(10)
print "Is node 1 a root? ", bst.isRoot(1)
print "Whats the tree height? ", bst.getHeight()
print "Is this tree BST? ", bst.isBST()
print "Is this tree balanced? ", bst.isBalanced()
print("Pre-order I: ", bst.preorder())
print("Pre-order II: ", bst.preorder2())
print("In-order: ", bst.inorder())
print("BFT: ", bst.BFT())