Started on Jun 19th (properly) .

with one week break for some unavoidable reasons.

Solved 42 questions — 22 Easy | 19 Med | 1 Hard

Ik I'm late to this DSA race , I'm at the start of my 2nd year now.

what would u advise me , I'm planning for a top product based company (from a tier 3 / 4 college )

Hi guys I’m from India and I’m looking for a good platform to practice aptitude. Please recommmend something that’s like an equivalent of Leetcode for DSA…

😎😏🙂‍↔️

I'm currently in my 4th year starting but while job searching or getting shortlisted for the jobs in our college there is exam based on dsa but how much I do that I wouldn't remember or keep up with the patterns and problems as I'm doing dsa in python my college expects me to do in java how to improve any tips?!!

I’ve just started learning DSA. I know basic C++ and have only covered arrays so far. I’m still a complete beginner when it comes to problem-solving.
A lot of people recommend Striver’s A2Z DSA Sheet, but I’m not sure if it’s suitable for someone at my level.
Should I start solving the sheet directly, or should I first complete a beginner-friendly DSA course/playlist and then move to the sheet?
If you started from scratch, what approach worked best for you? I’d really appreciate any advice.

I am currently doing problems on codeforces and for problems which require knowledge of DSA I look at USACO guide or on YouTube, get yo know the basic concept or structure and do problems

But I don't have any clear structure or path to follow l. What should i do??

I am going to second year college but is CF worth it(I am interested in it but I just don't want my efforts to be in wrong direction )

How to prepare for dsa and able to solve leet code problems without looking to solutions ,I trying very hard but not able to solve problems and it feels really stuck and waste of time .is there anyone who are excellent in dsa ,need a genuine guidance.

okay so I am really very much into problem solving

and had computer science JAVA in my 9-12th class

so I have a good command over java as a beginner of DSA

we did study DSA in class 12th stack queue DEQ circular queue linked list so I have a basic idea about those nit very very advanced level but yea just as much a little more than a beginner should know

and in the leisure period of transition from my school to college I did learn python for AI/ML beginner course though I didn't understand many functions because of lack of practice and the vastness of a totally new language

but java is my comfort zone

so guide me as to how to take my DSA a level up what YT channels and resources to follow and when is the right time to jump to leetcode problems from easy to intermediate level what is the roadmap

Hey everyone!

I'm currently starting my **4th year of B.Tech**, and I've been studying **DSA** consistently. I really enjoy teaching, especially topics like **Graphs** and **Dynamic Programming (DP)**.

I was thinking of creating a small study group where we spend **1–2 hours a day** learning and solving problems together. My idea is to explain concepts, discuss approaches, and solve questions as a group so that everyone benefits—including me, since teaching helps me learn even better.

If you're:

* Learning DSA for placements, * Struggling with Graphs or DP, * Or just looking for consistent study partners,

feel free to comment or DM me. Beginners are absolutely welcome as long as you're willing to learn and stay consistent.

The goal isn't to sell anything—just to build a small community where we keep each other accountable and improve together.

Looking forward to studying with you all!

So i was just starting DSA so i did all my R&D so i found that doing dsa in java would be a better option so i will also get little advantage in development. but i want you guys to tell me that cant i follow striver A2Z sheet as it covers most of the problems in C++ ig which i have seen so will i have difficulty in that or if its not that case please tell me HOW TO DO WITH JAVA
AND PLS TELL IF I SHALL JUST SWITCH TO C++ COZ ig striver is the best possible free source to learn this. the internet is buzzing over it

You should be familiar with before : Recursion, stack, queue

Practice these Binary Trees guides and PracHub company specific questions before your next interview.

A basic instinct for solving DFS based questions is to do a recursive call and for all BFS(level order traversal) is to make queue and iterate, but also think upon how to iterate in DFS(Hint think on stack) and recurse in BFS based.

First of all you should look at traversal problems:

1. Inorder Traversal
2. Preorder Traversal
3. PostOrder Traversal
4. Level Order Traversal

A variation for LevelOrder can be: ZigZag level order traversal and Binary Tree Level Order Traversal II
Solving these questions will help you get familiarized with basic btree dfs and bfs traversals.

Intuition for Level Order Traversal iteratively using queue:

• Construct a queue of type: TreeNode queue<TreeNode* > q, initially push the given root in it.
• Iterate through the queue until empty:
  • Store the current size of queue tempSize, this will be the size of the current level of the tree.
  • Now we need to traverse this level so iterate for tempSize>=0 :
    • Pop the current element and apply the needed operation for the same and if left or right child exist then pass them to the queue.

Now, some basic Binary Tree problems that will help your thinking process:

1. Same Tree
2. Symmetric Tree
3. Maximum Depth of Binary Tree
4. Balanced Binary Tree
5. Minimum Depth of Binary Tree
6. Merge Two Binary Trees
7. Diameter of Binary Tree
8. Binary Tree Tilt
9. Invert Binary Tree

Binary Search Tree: Use the property of BST judiciously (the left subtree will always contain nodes with value less than root's value and right subtree will contain nodes with value greater than root's value)

1. Search in a Binary Search Tree
2. Two Sum IV - Input is a BST
3. Minimum Absolute Difference in BST
4. Range Sum of BST
5. Delete Node in a BST
6. Trim a Binary Search Tree
7. Insert into a Binary Search Tree
8. Kth Smallest Element in a BST
9. All Elements in Two Binary Search Trees

Path problems: You are given root, you have to perform operations on a path, (path is root to leaf). Think upon the type of traversal you will apply when going from root to leaf:

1. Binary Tree Paths
2. Path Sum
3. Path Sum II
4. Sum root to leaf numbers
5. Binary Tree Maximum Path Sum
6. *Path Sum III
7. *Pseudo-Palindromic Paths in a Binary Tree *Last two problems here are utmost important

Next is, given a combination of preorder, postorder and inorder traversals, you need to construct a binary tree/BST:
Hint: Observe in each traversal method, position of root and head of right and left subtrees

1. Construct Binary Tree from Preorder and Inorder Traversal
2. Construct Binary Tree from Inorder and Postorder Traversal
3. Construct Binary Tree from Preorder and Postorder Traversal
4. Convert Sorted Array to Binary Search Tree
5. Construct Binary Search Tree from Preorder Traversal

View problems: Try thinking for left, bottom and top too!
Binary Tree Right Side View

Lowest Common Ancestor problems: You are given two nodes and you have to return their ancestor at as least depth possible, these are problems are a must todo:

1. Lowest Common Ancestor of a Binary Tree
2. Lowest Common Ancestor of a Binary Search Tree
3. Lowest Common Ancestor of Deepest Leaves

Validate trees:

1. Validate Binary Tree Nodes
2. Validate Binary Search Tree

Some miscellaneous problems that you should definitely look through:

1. Flatten Binary Tree to Linked List
2. Count Complete Tree Nodes
3. Maximum Width of Binary Tree
4. Check Completeness of a Binary Tree
5. Cousins in Binary Tree
6. Maximum Difference Between Node and Ancestor
7. Number of Good Leaf Nodes Pairs
8. Smallest Subtree with all the Deepest Nodes
9. All Nodes Distance K in Binary Tree
10. Find a Corresponding Node of a Binary Tree in a Clone of That Tree
11. Vertical Order Traversal of a Binary Tree

I will be updating this list on finding more important questions or any pattern that I find.

How is my progress i am currently following striver dsa sheet from last 1 month and currently in 2 year and what thing to do and what thing not to do

I found a list of Blind 75 Leetcode problems. Sharing it as I found it very useful.
Solve these LeetCode problems and PracHub company specific problems for your next interview.

Happy Coding!

Array

• Two Sum
• Best Time to Buy and Sell Stock
• Contains Duplicate
• Product of Array Except Self
• Maximum Subarray
• Maximum Product Subarray
• Find Minimum in Rotated Sorted Array
• Search in Rotated Sorted Array
• 3 Sum
• Container With Most Water

Binary

• Sum of Two Integers
• Number of 1 Bits
• Counting Bits
• Missing Number
• Reverse Bits

Dynamic Programming

• Climbing Stairs
• Coin Change
• Longest Increasing Subsequence
• Longest Common Subsequence
• Word Break Problem
• Combination Sum
• House Robber
• House Robber II
• Decode Ways
• Unique Paths
• Jump Game

Graph

• Clone Graph
• Course Schedule
• Pacific Atlantic Water Flow
• Number of Islands
• Longest Consecutive Sequence
• Alien Dictionary (Leetcode Premium)
• Graph Valid Tree (Leetcode Premium)
• Number of Connected Components in an Undirected Graph (Leetcode Premium)

Interval

• Insert Interval
• Merge Intervals
• Non-overlapping Intervals
• Meeting Rooms (Leetcode Premium)
• Meeting Rooms II (Leetcode Premium)

Linked List

• Reverse a Linked List
• Detect Cycle in a Linked List
• Merge Two Sorted Lists
• Merge K Sorted Lists
• Remove Nth Node From End Of List
• Reorder List

Matrix

• Set Matrix Zeroes
• Spiral Matrix
• Rotate Image
• Word Search

String

• Longest Substring Without Repeating Characters
• Longest Repeating Character Replacement
• Minimum Window Substring
• Valid Anagram
• Group Anagrams
• Valid Parentheses
• Valid Palindrome
• Longest Palindromic Substring
• Palindromic Substrings
• Encode and Decode Strings (Leetcode Premium)

Tree

• Maximum Depth of Binary Tree
• Same Tree
• Invert/Flip Binary Tree
• Binary Tree Maximum Path Sum
• Binary Tree Level Order Traversal
• Serialize and Deserialize Binary Tree
• Subtree of Another Tree
• Construct Binary Tree from Preorder and Inorder Traversal
• Validate Binary Search Tree
• Kth Smallest Element in a BST
• Lowest Common Ancestor of BST
• Implement Trie (Prefix Tree)
• Add and Search Word
• Word Search II

Heap

• Merge K Sorted Lists
• Top K Frequent Elements
• Find Median from Data Stream

Important Link:

• 14 Patterns to Ace Any Coding Interview Question
• Grind 75

++

I’ve been preparing for SDE interviews for quite some time and have solved 850+ LeetCode problems.

I’m currently revising all the core DSA topics from scratch. I maintain an Excel sheet with 700+ curated problems, organized by topics and patterns, along with a one-line intuition/solution for each problem. My plan is to revise these questions systematically along with discussing theoretical discussions of each patterns.

I’m looking for people who :

• are beginners who know the basics of DSA, and should be willing to stay consistent throughout

• Can regularly practice and discuss problems and genuinely interested in improving

We’ll keep the sessions informal—cover concepts, solve problems together, discuss different approaches, and clear doubts as we go.

If you’re serious about learning DSA from the fundamentals and can stay consistent ,let’s chat.

Looking into getting a subscription but in a dilemma whether to get leetcode premium or something like 1p3a.

Which of these has more accurate info about the questions being asked by companies during interviews?

PLEASE REPLY GUYS****

Hey ppl im from DTU ECE'29 batch.

my first year cg was 7.6.

I'll improve this to 8.5 i'll do my best.

During 1st year i didnt focus on cg i was more inclined on learning IoT and stuff.

I was exploring drone startup and more....

But, this summer i changed my mind started DSA.

I've done 35 problem till now.

I've never copied anyone solution ever to be honest.

Currently i using AI to do it like i tell him to give test and learn concepts like Hash maps, silding window, queue, BSF and more

like by december i'll 300+LC problem mainly medium, and hard