Increasing Order Search Tree | Leetcode 897 | BST | Day-17

[@soubhikroy9978]

mam thanks for regular this type of wonderful content

[@AyushiSharmaDSA]

Welcome Soubhik, glad you liked it :)

[@nishantgarg2815]

This is the most clean solution I've seen for this problem without creating new nodes. Good job.

[@AyushiSharmaDSA]

Thank you Nishant :)

[@LifestyleSoulDevu]

Thanks Ayushi for the series!

[@AyushiSharmaDSA]

Welcome Devanjali, glad you liked it :)

[@aahanaganjewar9951]

class Solution { ArrayList inorder = new ArrayList(); public TreeNode increasingBST(TreeNode root) { TreeNode dummy = new TreeNode(); TreeNode curr = dummy; utilTravel(root); for (TreeNode node : inorder) { curr.right = node; curr = curr.right; } return dummy.right; } public void utilTravel(TreeNode root) { if (root == null) { return; } utilTravel(root.left); TreeNode temp = new TreeNode(root.val); inorder.add(temp); utilTravel(root.right); } }

[@dhanrajlouvanshi7872]

Special Thanks for Providing java solutions

[@AyushiSharmaDSA]

Welcome Dhanraj :) Glad it is helpful :)

[@soubhikroy9978]

one more request mam can please discuss leetcode weekly contest question

[@AyushiSharmaDSA]

Hi Soubhik, yes everytime I think to make video, but then get stuck in some work. I'll surely try :)

[@sakshamsengar9798]

10:22 "otherwise i will make a left kol*******....... call " . highlight of the video 😂😂

[@amitsinha806]

you are always awesome 😎😎😎😎

[@AyushiSharmaDSA]

Thanks :)

[@rohitraj5832]

@Ayushi Sharma the same approach i've followed as yours, but am not getting the correct o/p.. plz have a look void inorder(TreeNode* root, TreeNode* temp){ if(root==NULL)return; inorder(root->left,temp); temp->right=root; temp=root; root->left=NULL; inorder(root->right,temp); } TreeNode* increasingBST(TreeNode* root) { TreeNode* dummy=new TreeNode(0); TreeNode* temp=dummy; inorder(root,temp); return dummy->right; }

[@tejaswigutta9017]

When we backtrack, temp is not updated as it is a local variable. Dry run it once you will understand @rohit raj

[@tejaswigutta9017]

class Solution { public TreeNode increasingBST(TreeNode root) { TreeNode dummy=new TreeNode(-1); convert(root,dummy); return dummy.right; } public TreeNode convert(TreeNode root,TreeNode dummy){ if(root==null) return dummy; TreeNode left=convert(root.left,dummy); left.right=root; left=root; left.left=null; return convert(root.right,left); } } This will work . Try to understand this :)

[@shekharchaugule7700]

that's great

[@AyushiSharmaDSA]

Thank you Shekhar :)

[@onlydharamsanatandharam]

thank you very much, when question are not going in mind and if that question's video found on your youtube channel than i'm free ... ki ab to ho jayega😎 thank u very much.

[@AyushiSharmaDSA]

thank you, glad it was helpful😄

[@aryangoyal2252]

I tried the same way but made helper function return aa treenode rather than making it void and globally declaring the curr. this made me confused what to return from helper function everytime and that's where I give up. thanks for this explanation.

[@AyushiSharmaDSA]

Yeah, first I also thought of doing that, but then I thought it's better to make global variable, this is how we learn :)

[@aryangoyal2252]

@@AyushiSharmaDSA yes mam , i will defineitly keep this in mind from next time.

[@ChandraShekhar-by3cd]

Thanks for great explanation. I had one small doubt regarding the use of `current ` as member variable. Is it the right way to define it??

[@AyushiSharmaDSA]

Welcome Chandra, Yes, but you can make it global variable as well :)

[@ChandraShekhar-by3cd]

@@AyushiSharmaDSA Ok, Thanks Ayushi.

[@dipanshmalhotra]

OP explaination didi helpes a lot (writing smj nhi aai pr approach aagai...XD)

[@AyushiSharmaDSA]

Thank you Dipansh :) aaj pta ni mouse ko kya hogya, chal hi nhi rha sahi se😂

[@amanbhadani8840]

Too much Easy 🙃

[@AyushiSharmaDSA]

✌🏻😊

[@divine5863]

Hii Didii.. can you give multiple solutions for problems on leetcode.. so that we can think in broader sense..

[@AyushiSharmaDSA]

Sure, thanks for valuable feedback. I'll take care from next video onwards 🙂

[@markandeysharma9771]

Mam should I take the course u buyed in 2year for cn???

[@AyushiSharmaDSA]

The course was good, if you want to buy, you can buy. I took dsa in cpp module

[@markandeysharma9771]

@@AyushiSharmaDSA sure but I going through anuj bhaiya is it okay ??

[@AyushiSharmaDSA]

@@markandeysharma9771 sorry i haven't seen the content, so can't say anything. :)

[@markandeysharma9771]

@@AyushiSharmaDSA sure

[@dipanshmalhotra]

eagerly waitinng for new video didi where is new video.

[@AyushiSharmaDSA]

Hi Dipansh, will upload in some time, sorry for delay :)

[@dipanshmalhotra]

@@AyushiSharmaDSA koi nhi didi its ok i tried question and finally in the world i solved the trees question:)

[@AyushiSharmaDSA]

@@dipanshmalhotra awsm🙌🏻🙌🏻🙌🏻🔥

[@corporatebhai1703]

why are we doing node->left=NULL didn't understand

[@AyushiSharmaDSA]

see because in result tree, for every node, left is null.

[@corporatebhai1703]

@@AyushiSharmaDSA shouldn't we do current->left=null then as that is the tree we are returning

[@AyushiSharmaDSA]

@@corporatebhai1703 we can do that also :) like this void helper(TreeNode* node) { if(node == NULL) { return; } helper(node->left); current->right = node; current = node; current->left = NULL; helper(node->right); }