# New Year Gift - Curated List of Top 75 LeetCode Questions to Save Your Time

New Year Gift to every fellow time-constrained engineer out there looking for a job, here's a list of the best LeetCode questions that teach you core concepts and techniques for each category/type of problems! Many other LeetCode questions are a mash of the techniques from these individual questions. I used this list in my last job hunt to only do the important questions.

Good luck and Happy New Year!

Array

- Two Sum - https://leetcode.com/problems/two-sum/
- Contains Duplicate - https://leetcode.com/problems/contains-duplicate/
- Product of Array Except Self - https://leetcode.com/problems/product-of-array-except-self/
- Maximum Subarray - https://leetcode.com/problems/maximum-subarray/
- Maximum Product Subarray - https://leetcode.com/problems/maximum-product-subarray/
- Find Minimum in Rotated Sorted Array - https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/
- Search in Rotated Sorted Array - https://leetcode.com/problems/search-in-rotated-sorted-array/
- 3Sum - https://leetcode.com/problems/3sum/
- Container With Most Water - https://leetcode.com/problems/container-with-most-water/

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Binary

- Sum of Two Integers - https://leetcode.com/problems/sum-of-two-integers/
- Number of 1 Bits - https://leetcode.com/problems/number-of-1-bits/
- Counting Bits - https://leetcode.com/problems/counting-bits/
- Missing Number - https://leetcode.com/problems/missing-number/
- Reverse Bits - https://leetcode.com/problems/reverse-bits/

---

Dynamic Programming

- Climbing Stairs - https://leetcode.com/problems/climbing-stairs/
- Coin Change - https://leetcode.com/problems/coin-change/
- Longest Increasing Subsequence - https://leetcode.com/problems/longest-increasing-subsequence/
- Longest Common Subsequence -
- Word Break Problem - https://leetcode.com/problems/word-break/
- Combination Sum - https://leetcode.com/problems/combination-sum-iv/
- House Robber - https://leetcode.com/problems/house-robber/
- House Robber II - https://leetcode.com/problems/house-robber-ii/
- Decode Ways - https://leetcode.com/problems/decode-ways/
- Unique Paths - https://leetcode.com/problems/unique-paths/
- Jump Game - https://leetcode.com/problems/jump-game/

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Graph

- Clone Graph - https://leetcode.com/problems/clone-graph/
- Course Schedule - https://leetcode.com/problems/course-schedule/
- Pacific Atlantic Water Flow - https://leetcode.com/problems/pacific-atlantic-water-flow/
- Number of Islands - https://leetcode.com/problems/number-of-islands/
- Longest Consecutive Sequence - https://leetcode.com/problems/longest-consecutive-sequence/
- Alien Dictionary (Leetcode Premium) - https://leetcode.com/problems/alien-dictionary/
- Graph Valid Tree (Leetcode Premium) - https://leetcode.com/problems/graph-valid-tree/
- Number of Connected Components in an Undirected Graph (Leetcode Premium) - https://leetcode.com/problems/number-of-connected-components-in-an-undirected-graph/

---

Interval

- Insert Interval - https://leetcode.com/problems/insert-interval/
- Merge Intervals - https://leetcode.com/problems/merge-intervals/
- Non-overlapping Intervals - https://leetcode.com/problems/non-overlapping-intervals/
- Meeting Rooms (Leetcode Premium) - https://leetcode.com/problems/meeting-rooms/
- Meeting Rooms II (Leetcode Premium) - https://leetcode.com/problems/meeting-rooms-ii/

---

- Merge Two Sorted Lists - https://leetcode.com/problems/merge-two-sorted-lists/
- Merge K Sorted Lists - https://leetcode.com/problems/merge-k-sorted-lists/
- Remove Nth Node From End Of List - https://leetcode.com/problems/remove-nth-node-from-end-of-list/
- Reorder List - https://leetcode.com/problems/reorder-list/

---

Matrix

- Set Matrix Zeroes - https://leetcode.com/problems/set-matrix-zeroes/
- Spiral Matrix - https://leetcode.com/problems/spiral-matrix/
- Rotate Image - https://leetcode.com/problems/rotate-image/
- Word Search - https://leetcode.com/problems/word-search/

---

String

- Longest Substring Without Repeating Characters - https://leetcode.com/problems/longest-substring-without-repeating-characters/
- Longest Repeating Character Replacement - https://leetcode.com/problems/longest-repeating-character-replacement/
- Minimum Window Substring - https://leetcode.com/problems/minimum-window-substring/
- Valid Anagram - https://leetcode.com/problems/valid-anagram/
- Group Anagrams - https://leetcode.com/problems/group-anagrams/
- Valid Parentheses - https://leetcode.com/problems/valid-parentheses/
- Valid Palindrome - https://leetcode.com/problems/valid-palindrome/
- Longest Palindromic Substring - https://leetcode.com/problems/longest-palindromic-substring/
- Palindromic Substrings - https://leetcode.com/problems/palindromic-substrings/
- Encode and Decode Strings (Leetcode Premium) - https://leetcode.com/problems/encode-and-decode-strings/

---

Tree

- Maximum Depth of Binary Tree - https://leetcode.com/problems/maximum-depth-of-binary-tree/
- Same Tree - https://leetcode.com/problems/same-tree/
- Invert/Flip Binary Tree - https://leetcode.com/problems/invert-binary-tree/
- Binary Tree Maximum Path Sum - https://leetcode.com/problems/binary-tree-maximum-path-sum/
- Binary Tree Level Order Traversal - https://leetcode.com/problems/binary-tree-level-order-traversal/
- Serialize and Deserialize Binary Tree - https://leetcode.com/problems/serialize-and-deserialize-binary-tree/
- Subtree of Another Tree - https://leetcode.com/problems/subtree-of-another-tree/
- Construct Binary Tree from Preorder and Inorder Traversal - https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/
- Validate Binary Search Tree - https://leetcode.com/problems/validate-binary-search-tree/
- Kth Smallest Element in a BST - https://leetcode.com/problems/kth-smallest-element-in-a-bst/
- Lowest Common Ancestor of BST - https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/
- Implement Trie (Prefix Tree) - https://leetcode.com/problems/implement-trie-prefix-tree/
- Word Search II - https://leetcode.com/problems/word-search-ii/

---

Heap

- Merge K Sorted Lists - https://leetcode.com/problems/merge-k-sorted-lists/
- Top K Frequent Elements - https://leetcode.com/problems/top-k-frequent-elements/
- Find Median from Data Stream - https://leetcode.com/problems/find-median-from-data-stream/

You're welcome!

• Apple
What is the basis of this short list? How did you come up with the list? What is the criteria?
Dec 31, 2018 2
OP
I did 400-500 LC questions last time and distilled the most useful questions from my experience into this list.
Dec 31, 2018
• Apple
Ok, thank you
Dec 31, 2018
• Cisco jgudvruv
Let the grind begin
Dec 30, 2018 0
• Vertivco / Eng
Sir.
Sir.
You forgot Cherry Picking #741.
Dec 30, 2018 0
• New srjJ86
Have done about 500 and I approve this!
Jul 24 9
• Microsoft leetlleet
Thanks for the reply. How about coding round? I am at 120 and trying to figure out how many will be good enough. Did you feel that you are passing the coding rounds with flying color?
Aug 3
• New srjJ86
If you are not unlucky they dont ask very tricky questions, at least I havent got. Mostly mediums were asked. If you can solve mediums comfortably in each category hopefully you are good to go. Fankly if tricky questions are asked where you need special tricks to solve it, its higly unlikely someone will be able to solve it if not seen that before, specially considering interview pressure situation.
Aug 3
• New srjJ86
One more thing I can add. Nothing can beat practice. The more you practice the more you will see the patterns. You just need to see the pattern to nail a problem and it comes from practice. Solving X amount gives that exposure, more you solve its better.
Aug 3
• Microsoft leetlleet
Thanks!
Aug 4
Hey Srj, have you decided where to go? Any update (lesson learned type)?
Aug 24
• New 2xtc
In Leetcode list form: https://leetcode.com/list/xoqag3yj/
May 3 1
• eBay / Eng gkhldncjs
but there are only 74 of them :(

never mind, I don't have a premium account
Aug 13
• Microsoft 🐟FishyFish
Thank you! I’m brushing up algo for google interview
Dec 31, 2018 7
• Oracle / Eng NUkX62
+1
Jan 7
• Oath
enough for G if you deeply understand how to solve each of the above problems, although I’ve heard EMEA and APAC area G interviews are harder so might not be enough for those

P.S : passed HC recently , above list covers all areas
Feb 17
• Oracle blahbl
Google APAC is fucking crazy! I cracked it a couple of years ago and hands down the toughest interview I’ve ever faced.
Feb 17
• Dematic / Eng Larry Cook
What’s APAC?
Aug 16
• New tbTO28
Asia Pacific
Aug 29
• Is this good enough for Facebook onsite?
Jul 26 5
• Intel gtfo2019
No
Jul 26
• Yes !
I received an offer from FB!
Aug 13
Hey blindboy congrats! May I ask you how many you solved in total (lifetime)? How many tagged FB questions? Or did you only solve the ones here?
Aug 24
• Thanks whatchado! Apologies for the very late reply. Overall, I have solved 158 questions on Leetcode, Easy 75, Medium 75 and Hard 8. This includes the above list (not the premium ones, for which I used the other leet website ;)).
Besides, I have also solved a few more from other websites. I think the key is to solve problems obsessively for a week or so right before the interviews.
Good Luck !
Oct 16
• Capital One / Eng
What other leetsite you used @blind_boy?
Nov 7
This legit af OP. Now I can just practice these few before interviewing lol. You the real tech lead!
Dec 31, 2018 3
• New / Eng
Sep 22
• Indeed / Eng uPrj01
Also Intrigued
Nov 1
• New TuRA70
lmao following
Nov 7
• Aurora bystander!
Nerds are orgasming!
Peace bro...
Dec 30, 2018 0
• Microsoft meanwhile
Aug 3 1
• Jetblack
🤣
Aug 3
• Mentor Graphics vAjo15
You are the hero that blind don’t deserve
Dec 30, 2018 0
• Ericsson / Eng FriedFish1
Saved.. you’re a god 🙏
Dec 30, 2018 0
• Microsoft / Eng Sbhdu
Great effort OP.
Imo most of these are already covered in the leetcode's most liked questions list and the amazon list.
Dec 31, 2018 2
OP
They must have been inspired by my list. My list was published and open sourced since a year ago ;)
Dec 31, 2018
• Microsoft jefgfi
Can u give us the link to it op?
Dec 31, 2018
• Comcast onlytroll
If this helps me get through to FANG+, I'm going to hunt you down, and buy you a round 🍻kind stranger!
Aug 24 1
• Indeed / Eng uPrj01
Did it work?
Nov 19
• Groupon randomusr0
I created a CSV out of it - https://pastebin.com/zneJ2NbD
Apr 30 0
• Microsoft PNlg17
Anyone used these to get senior (l5) at google? Are they too easy?
Apr 30 0
• Microsoft UMbR3
You're my Jesus
Dec 31, 2018 0
• New / Eng abuhr3i
Where are the remaining 25?
Feb 25 0
• PayPal jLeT47
Thanks op to compile the list. But there are 75 questions mentioned in the list. Did you miss pasting the remaining 25?
Feb 17 0