Boundary traversal of binary tree (Border Elements)

Find all the nodes on the boundary and print them. That is the boundary order traversal of binary tree.

[@surajjha5542]

Nice video , just a minor correction : print root node first and then pass root's left to the print_left function .
Otherwise it will fail for a tree having only right nodes.

[@CodeSuccessChronicle]

The way he says Hello friends itself takes my anxiety away.. Thank you for your efforts.

[@meghasharma3092]

Just can't tell , how good you are ! Your videos have been really helpful for me in preparing for data structures interviews..! :)

[@arpitgupta1143]

Your explanation is nice... but if the tree is skewed it will print the boundary elements multiple times.

[@sandhyagupta7359]

true

[@aakashparmar560]

Sir just want to say thank you for this wonderful video. You are OP sir...........

[@JJ-Bond]

this is a very great explanation, I appreciate all of your videos.
a small thing
1. root needs to be dealt with independently before process left and right subtree

[@minirasamedova648]

You are genius!! Thank you so much for a simple explanation

[@kasyapdharanikota8570]

very well explained sir, thank you for detailed explanation

[@Algo_Guru]

Hi Vivekanand, very clear explanation..Thanks. One request, could you please also mention some use cases (applications) of each of the traversals? This would motivate the viewers.

[@sandeepsinghnegi3644]

can you make a series on solving the competitive programming question

[@anindyasundarhazra2523]

Plz sir

[@karthikrashinkar204]

Can I say that we need to find
1) left view of binary tree
2) right view of binary tree
3) find leaf nood of binary tree ?

[@RahulKashyap-yv5ox]

no

[@_ADITIKAJALE]

@@RahulKashyap-yv5ox why?

[@AlancRodriguez]

Superb explanation!

[@chrisy.703]

really really good man!

[@edwardteach2]

Thanks, my python implementation:
# Definition for a binary tree node.
# class TreeNode(object):
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution(object):
def __init__(self):
self.root = []
self.lb = []
self.rb = []
self.leaves = []
def boundaryOfBinaryTree(self, root):
"""
:type root: TreeNode
:rtype: List[int]
"""
if not root:
return root
self.root.append(root.val)
self.left_bdr(root.left)
self.leaf(root.left)
self.leaf(root.right)
self.right_bdr(root.right)
return self.root + self.lb + self.leaves + self.rb[::-1]
def left_bdr(self, root):
if root:
if root.left:
self.lb.append(root.val)
self.left_bdr(root.left)
elif root.right:
self.lb.append(root.val)
self.left_bdr(root.right)
def right_bdr(self, root):
if root:
if root.right:
self.rb.append(root.val)
self.right_bdr(root.right)
elif root.left:
self.rb.append(root.val)
self.right_bdr(root.left)
def leaf(self, root):
if root:
self.leaf(root.left)
self.leaf(root.right)
if not root.left and not root.right:
self.leaves.append(root.val)

[@ibrahimshaikh3642]

Nice video,also please mention Time complexity for algorithm

[@amitranjan6998]

in the left tree recursion ,if e finishes the recursion stack then after some time it go back to C and from C it look ,it's have right subtree or not ,it have so it add C again

[@roshanraut3093]

Requires to change the position of print in print_right function.

[@harshanand4018]

In Right Boundary Condition,there is a correction. First we need to traverse to right child and then print the data.

[@user-mo1vm2nt7l]

You are really awesome dude

[@Sarojkumar-yh9uy]

awsome sir

[@Sarojkumar-yh9uy]

sorry sir ,
not working for right skew tree

[@feisuxiaozhu]

very clear, thanks a lot!

[@mahipalsingh-yo4jt]

return "very well explained" ;

[@jeeveshkataria6439]

wrong, Not work for skew trees

[@DeepakGupta-zz1vf]

Sir there are many videos which are not added in playlist, Can you please add it

[@ganeshiitr-cse6328]

Thanks ....

[@PradeepSingh-ov3bt]

the error lies using 2 "if" instead of 1 if and 1 else if

[@aayush5474]

you need an extra condition to check if the tree is skewed otherwise the code will fail

[@vash721]

Sir can you plz explain the M-way search tree ........

[@aashutoshvatsa5152]

can u please provide quick sorting and merge sorting .

[@deepakgoyal589]

Sir can u explain rope data structure please

[@railgang5026]

Plz solve postorder traversal from
Given in order,preorder

[@user-mo1vm2nt7l]

Sir your code is wrong it does not work for input (15,10,8,12,13,20,17,25)

[@285ravi]

its not printing in correct order, to get correct order,in right view all the printing statements should be just below of recursive calling function.

[@vikasbajpai3013]

wrong code

[@user-zj9pq5xc7x]

you could have easily gone anticlockwise...this doesn't make much sense, sorry