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Mohammad Fraz · LeadCoding
Fraz DSA Sheet
Pattern-based practice from the LeadCoding problem sheet.
315 practice entries · Source checked
0 / 315 completed0%
About this source edition
Creator-published expanded spreadsheet
“Source checked” is when this edition was retrieved, not a claim that the creator updated it then.
Original sheet ↗Arrays
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Two Sum | Easy | Open ↗ | ||
| Best Time To Buy And Sell Stock | Easy | Open ↗ | ||
| Merge Sorted Array | Easy | Open ↗ | ||
| Move Zeroes | Easy | Open ↗ | ||
| Best Time To Buy And Sell Stock Ii | Easy | Open ↗ | ||
| Running Sum Of 1D Array | Easy | Open ↗ | — | |
| Find Pivot Index | Easy | Open ↗ | — | |
| Majority Element | Easy | Open ↗ | ||
| Fibonacci Number | Easy | Open ↗ | ||
| Squares Of A Sorted Array | Easy | Open ↗ | — | |
| Pascals Triangle | Easy | Open ↗ | — | |
| Remove Duplicates From Sorted Array | Easy | Open ↗ | — | |
| Merge Intervals | Medium | Open ↗ | — | |
| 3Sum | Medium | Open ↗ | ||
| Product Of Array Except Self | Medium | Open ↗ | ||
| Insert Delete Getrandom O1 | Medium | Open ↗ | — | |
| Subarray Sum Equals K | Medium | Open ↗ | — | |
| Next Permutation | Medium | Open ↗ | — | |
| Spiral Matrix | Medium | Open ↗ | — | |
| Container With Most Water | Medium | Open ↗ | — | |
| Rotate Image | Medium | Open ↗ | — | |
| Word Search | Medium | Open ↗ | ||
| 3Sum Closest | Medium | Open ↗ | — | |
| Game Of Life | Medium | Open ↗ | — | |
| Pairs Of Songs With Total Durations Divisible By 60 | Medium | Open ↗ | — | |
| 4Sum | Medium | Open ↗ | ||
| Find The Duplicate Number | Medium | Open ↗ | — | |
| Combination Sum | Medium | Open ↗ | ||
| Jump Game Ii | Medium | Open ↗ | ||
| Maximum Points You Can Obtain From Cards | Medium | Open ↗ | — | |
| Maximum Area Of A Piece Of Cake After Horizontal And Vertical Cuts | Medium | Open ↗ | — | |
| Max Area Of Island | Medium | Open ↗ | — | |
| Find All Duplicates In An Array | Medium | Open ↗ | — | |
| K Diff Pairs In An Array | Medium | Open ↗ | — | |
| Subsets | Medium | Open ↗ | ||
| Invalid Transactions | Medium | Open ↗ | — | |
| Jump Game | Medium | Open ↗ | — | |
| Subarray Sums Divisible By K | Medium | Open ↗ | — | |
| First Missing Positive | Hard | Open ↗ | — | |
| Largest Rectangle In Histogram | Hard | Open ↗ | — | |
| Insert Delete Getrandom O1 Duplicates Allowed | Hard | Open ↗ | — | |
| Best Time To Buy And Sell Stock Iii | Hard | Open ↗ | ||
| Max Value Of Equation | Hard | Open ↗ |
3- What is a recursion tree
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6- General Steps to recursion problems
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| 7- https://leetcode.com/problems/subsets/ | Hard | Open ↗ | ||
| 8- https://leetcode.com/problems/permutations/ | Hard | Open ↗ | ||
| 9- https://leetcode.com/problems/permutations-ii/ | Hard | Open ↗ | ||
| 10- https://leetcode.com/problems/subsets-ii/ | Hard | Open ↗ | ||
| 11- https://leetcode.com/problems/combinations/ | Hard | Open ↗ | ||
| 12- https://leetcode.com/problems/combination-sum/ | Hard | Open ↗ | ||
| 13- https://leetcode.com/problems/combination-sum-ii/ | Hard | Open ↗ | ||
| 14- https://leetcode.com/problems/combination-sum-iii/ | Hard | Open ↗ | ||
| 15- https://leetcode.com/problems/letter-combinations-of-a-phone-number/ | Hard | Open ↗ | ||
| 16- https://leetcode.com/problems/partition-to-k-equal-sum-subsets/ | Hard | Open ↗ | ||
| 17- https://leetcode.com/problems/maximum-length-of-a-concatenated-string-with-unique-characters/ | Hard | Open ↗ | ||
| 18- https://leetcode.com/problems/flood-fill/ | Hard | Open ↗ | ||
| 19- https://leetcode.com/problems/word-search/ | Hard | Open ↗ |
20- Rat in a Maze
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| 21- https://leetcode.com/problems/n-queens/ | Hard | Open ↗ |
DYNAMIC PROGRAMING
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Maximum Subarray | Easy | Open ↗ | — | |
| Climbing Stairs | Easy | Open ↗ | — | |
| Divisor Game | Easy | Open ↗ | ||
| Counting Bits | Easy | Open ↗ | — | |
| Decode Ways | Medium | Open ↗ | ||
| Word Break | Medium | Open ↗ | ||
| Delete And Earn | Medium | Open ↗ | — | |
| Maximal Square | Medium | Open ↗ | — | |
| Coin Change | Medium | Open ↗ | — | |
| Maximum Product Subarray | Medium | Open ↗ | — | |
| Maximum Length Of Repeated Subarray | Medium | Open ↗ | — | |
| Palindromic Substrings | Medium | Open ↗ | — | |
| House Robber | Medium | Open ↗ | ||
| Continuous Subarray Sum | Medium | Open ↗ | — | |
| Knight Dialer | Medium | Open ↗ | — | |
| Longest Increasing Subsequence | Medium | Open ↗ | — | |
| Unique Paths | Medium | Open ↗ | — | |
| Count Square Submatrices With All Ones | Medium | Open ↗ | — | |
| Range Sum Query 2D Immutable | Medium | Open ↗ | — | |
| Longest Arithmetic Subsequence | Medium | Open ↗ | — | |
| Trapping Rain Water | Hard | Open ↗ | — | |
| Word Break Ii | Hard | Open ↗ | — | |
| Regular Expression Matching | Hard | Open ↗ | — | |
| Maximal Rectangle | Hard | Open ↗ | — | |
| Longest Valid Parentheses | Hard | Open ↗ | — | |
| Edit Distance | Hard | Open ↗ | — | |
| Minimum Difficulty Of A Job Schedule | Hard | Open ↗ | — | |
| Frog Jump | Hard | Open ↗ | — | |
| Best Time To Buy And Sell Stock Iv | Hard | Open ↗ | ||
| Burst Balloons | Hard | Open ↗ | — | |
| Minimum Cost To Merge Stones | Hard | Open ↗ | — | |
| Minimum Insertion Steps To Make A String Palindrome | Hard | Open ↗ | — | |
| Super Egg Drop | Hard | Open ↗ | — | |
| Count Different Palindromic Subsequences | Hard | Open ↗ | — | |
| Minimum Cost To Cut A Stick | Hard | Open ↗ | — |
STRINGS
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Add Strings | Easy | Open ↗ | — | |
| Longest Common Prefix | Easy | Open ↗ | — | |
| Valid Palindrome Ii | Easy | Open ↗ | — | |
| Roman To Integer | Easy | Open ↗ | — | |
| Implement Strstr | Easy | Open ↗ | — | |
| Longest Substring Without Repeating Characters | Medium | Open ↗ | — | |
| Minimum Remove To Make Valid Parentheses | Medium | Open ↗ | — | |
| Longest Palindromic Substring | Medium | Open ↗ | — | |
| Group Anagrams | Medium | Open ↗ | ||
| Generate Parentheses | Medium | Open ↗ | — | |
| Basic Calculator Ii | Medium | Open ↗ | — | |
| Integer To Roman | Medium | Open ↗ | — | |
| Reverse Words In A String | Medium | Open ↗ | — | |
| Simplify Path | Medium | Open ↗ | — | |
| Zigzag Conversion | Medium | Open ↗ | — | |
| Text Justification | Hard | Open ↗ | — | |
| Integer To English Words | Hard | Open ↗ | — | |
| Minimum Window Substring | Hard | Open ↗ | — | |
| Valid Number | Hard | Open ↗ | — | |
| Distinct Subsequences | Hard | Open ↗ | — | |
| Smallest Range Covering Elements From K Lists | Hard | Open ↗ | — | |
| Substring With Concatenation Of All Words | Hard | Open ↗ | — |
MATHS
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Reverse Integer | Easy | Open ↗ | — | |
| Add Binary | Easy | Open ↗ | — | |
| Palindrome Number | Easy | Open ↗ | — | |
| Minimum Moves To Equal Array Elements | Easy | Open ↗ | — | |
| Happy Number | Easy | Open ↗ | ||
| Excel Sheet Column Title | Easy | Open ↗ | — | |
| Missing Number | Easy | Open ↗ | — | |
| Maximum Product Of Three Numbers | Easy | Open ↗ | — | |
| Power Of Two | Easy | Open ↗ | — | |
| Encode And Decode Tinyurl | Medium | Open ↗ | — | |
| String To Integer Atoi | Medium | Open ↗ | — | |
| Multiply Strings | Medium | Open ↗ | — | |
| Angle Between Hands Of A Clock | Medium | Open ↗ | — | |
| Integer Break | Medium | Open ↗ | — | |
| Valid Square | Medium | Open ↗ | — | |
| The Kth Factor Of N | Medium | Open ↗ | — | |
| Basic Calculator | Hard | Open ↗ | — | |
| Max Points On A Line | Hard | Open ↗ | — | |
| Permutation Sequence | Hard | Open ↗ | — | |
| Number Of Digit One | Hard | Open ↗ | — |
THAT WOULD BE TOO EASY FOR YOU , LETS DO MEDIUM
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Task Scheduler | Medium | Open ↗ | — | |
| Gas Station | Medium | Open ↗ | — | |
| Minimum Deletion Cost To Avoid Repeating Letters | Medium | Open ↗ | — | |
| Maximum Number Of Events That Can Be Attended | Medium | Open ↗ | — | |
| Minimum Deletions To Make Character Frequencies Unique | Medium | Open ↗ | — | |
| Remove K Digits | Medium | Open ↗ | — | |
| Restore The Array From Adjacent Pairs | Medium | Open ↗ | — | |
| Non Overlapping Intervals | Medium | Open ↗ | — | |
| Candy | Hard | Open ↗ | — | |
| Minimum Number Of Taps To Open To Water A Garden | Hard | Open ↗ | — | |
| Create Maximum Number | Hard | Open ↗ | — |
DFS
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Letter Combinations Of A Phone Number | Medium | Open ↗ | ||
| Course Schedule Ii | Medium | Open ↗ | — | |
| Decode String | Medium | Open ↗ | — | |
| Number Of Provinces | Medium | Open ↗ | — | |
| Clone Graph | Medium | Open ↗ | — | |
| Shortest Bridge | Medium | Open ↗ | — | |
| All Paths From Source To Target | Medium | Open ↗ | — | |
| Surrounded Regions | Medium | Open ↗ | — | |
| House Robber Iii | Medium | Open ↗ | — | |
| Critical Connections In A Network | Hard | Open ↗ | — | |
| Remove Invalid Parentheses | Hard | Open ↗ | — | |
| Longest Increasing Path In A Matrix | Hard | Open ↗ | — | |
| Concatenated Words | Hard | Open ↗ | — | |
| Making A Large Island | Hard | Open ↗ | — | |
| Contain Virus | Hard | Open ↗ | — | |
| 24 Game | Hard | Open ↗ | — | |
| Remove Boxes | Hard | Open ↗ | — |
TREE
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Diameter Of Binary Tree | Easy | Open ↗ | — | |
| Invert Binary Tree | Easy | Open ↗ | — | |
| Subtree Of Another Tree | Easy | Open ↗ | — | |
| Range Sum Of Bst | Easy | Open ↗ | — | |
| Symmetric Tree | Easy | Open ↗ | — | |
| Convert Sorted Array To Binary Search Tree | Easy | Open ↗ | — | |
| Merge Two Binary Trees | Easy | Open ↗ | — | |
| Maximum Depth Of Binary Tree | Easy | Open ↗ | — | |
| Binary Tree Paths | Easy | Open ↗ | — | |
| Same Tree | Easy | Open ↗ | — | |
| Lowest Common Ancestor Of A Binary Search Tree | Easy | Open ↗ | — | |
| Path Sum | Easy | Open ↗ | — | |
| Minimum Absolute Difference In Bst | Easy | Open ↗ | — | |
| Sum Of Left Leaves | Easy | Open ↗ | — | |
| Balanced Binary Tree | Easy | Open ↗ | — | |
| Binary Tree Inorder Traversal | Easy | Open ↗ | — | |
| Count Good Nodes In Binary Tree | Medium | Open ↗ | — | |
| Lowest Common Ancestor Of A Binary Tree | Medium | Open ↗ | — | |
| Binary Tree Right Side View | Medium | Open ↗ | — | |
| All Nodes Distance K In Binary Tree | Medium | Open ↗ | — | |
| Validate Binary Search Tree | Medium | Open ↗ | — | |
| Binary Tree Zigzag Level Order Traversal | Medium | Open ↗ | — | |
| Binary Search Tree Iterator | Medium | Open ↗ | — | |
| Binary Tree Level Order Traversal | Medium | Open ↗ | — | |
| Path Sum Iii | Medium | Open ↗ | — | |
| Construct Binary Tree From Preorder And Postorder Traversal | Medium | Open ↗ | — | |
| Unique Binary Search Trees | Medium | Open ↗ | — | |
| Recover Binary Search Tree | Medium | Open ↗ | — | |
| Populating Next Right Pointers In Each Node | Medium | Open ↗ | — | |
| Flatten Binary Tree To Linked List | Medium | Open ↗ | — | |
| Maximum Width Of Binary Tree | Medium | Open ↗ | — | |
| Unique Binary Search Trees Ii | Medium | Open ↗ | — | |
| Kth Smallest Element In A Bst | Medium | Open ↗ | — | |
| Redundant Connection | Medium | Open ↗ | — | |
| Serialize And Deserialize Binary Tree | Hard | Open ↗ | — | |
| Binary Tree Maximum Path Sum | Hard | Open ↗ | — | |
| Vertical Order Traversal Of A Binary Tree | Hard | Open ↗ | — | |
| Binary Tree Cameras | Hard | Open ↗ | — | |
| Sum Of Distances In Tree | Hard | Open ↗ | — | |
| Number Of Ways To Reconstruct A Tree | Hard | Open ↗ | — | |
| Redundant Connection Ii | Hard | Open ↗ | — |
HASH TABLE
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BINARY SEARCH
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Sqrtx | Easy | Open ↗ | — | |
| Binary Search | Easy | Open ↗ | — | |
| Count Negative Numbers In A Sorted Matrix | Easy | Open ↗ | — | |
| Peak Index In A Mountain Array | Easy | Open ↗ | — | |
| Time Based Key Value Store | Medium | Open ↗ | — | |
| Search In Rotated Sorted Array | Medium | Open ↗ | — | |
| Powx N | Medium | Open ↗ | ||
| Find First And Last Position Of Element In Sorted Array | Medium | Open ↗ | — | |
| Find Peak Element | Medium | Open ↗ | — | |
| Search A 2D Matrix | Medium | Open ↗ | — | |
| Divide Two Integers | Medium | Open ↗ | — | |
| Capacity To Ship Packages Within D Days | Medium | Open ↗ | — | |
| Minimum Limit Of Balls In A Bag | Medium | Open ↗ | — | |
| Median Of Two Sorted Arrays | Hard | Open ↗ | — | |
| Count Of Smaller Numbers After Self | Hard | Open ↗ | — | |
| Max Sum Of Rectangle No Larger Than K | Hard | Open ↗ | — | |
| Split Array Largest Sum | Hard | Open ↗ | — | |
| Shortest Subarray With Sum At Least K | Hard | Open ↗ | — |
BFS
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Number Of Islands | Medium | Open ↗ | — | |
| Rotting Oranges | Medium | Open ↗ | — | |
| Snakes And Ladders | Medium | Open ↗ | — | |
| Is Graph Bipartite | Medium | Open ↗ | — | |
| Minimum Jumps To Reach Home | Medium | Open ↗ | — | |
| Word Ladder | Hard | Open ↗ | — | |
| Word Ladder Ii | Hard | Open ↗ | — | |
| Cut Off Trees For Golf Event | Hard | Open ↗ | — | |
| Reachable Nodes In Subdivided Graph | Hard | Open ↗ | — |
MEDIUM / HARD
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Partition Labels | Hard | Open ↗ | — | |
| Sort Colors | Hard | Open ↗ | — | |
| Longest Repeating Character Replacement | Hard | Open ↗ | — | |
| Maximum Number Of Visible Points | Hard | Open ↗ | — | |
| Subarrays With K Different Integers | Hard | Open ↗ | — | |
| Lru Cache | Medium | Open ↗ | — | |
| Find Median From Data Stream | Medium | Open ↗ | — | |
| Design Underground System | Medium | Open ↗ | — | |
| Lfu Cache | Medium | Open ↗ | — | |
| Tweet Counts Per Frequency | Medium | Open ↗ | — | |
| All Oone Data Structure | Medium | Open ↗ | — | |
| Design Browser History | Medium | Open ↗ |
STACK
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PRE , POST , INORDER TRAVERSALS OF BINARY TREE
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Implement Stack Using Queues | Easy | Open ↗ | — | |
| Implement Stack Using Queues | Medium | Open ↗ | — | |
| Daily Temperatures | Medium | Open ↗ | — | |
| Flatten Nested List Iterator | Medium | Open ↗ | — | |
| Online Stock Span | Medium | Open ↗ | — | |
| Minimum Cost Tree From Leaf Values | Medium | Open ↗ | — | |
| Sum Of Subarray Minimums | Medium | Open ↗ | ||
| Evaluate Reverse Polish Notation | Medium | Open ↗ | — |
GRAPH
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| Employee Importance | Easy | Open ↗ | — | |
| Find The Town Judge | Easy | Open ↗ | — | |
| Evaluate Division | Medium | Open ↗ | — | |
| Accounts Merge | Medium | Open ↗ | — | |
| Network Delay Time | Medium | Open ↗ | — | |
| Find Eventual Safe States | Medium | Open ↗ | — | |
| Keys And Rooms | Medium | Open ↗ | — | |
| Possible Bipartition | Medium | Open ↗ | — | |
| Most Stones Removed With Same Row Or Column | Medium | Open ↗ | — | |
| Regions Cut By Slashes | Medium | Open ↗ | — | |
| Satisfiability Of Equality Equations | Medium | Open ↗ | — | |
| As Far From Land As Possible | Medium | Open ↗ | — | |
| Number Of Closed Islands | Medium | Open ↗ | — | |
| Number Of Operations To Make Network Connected | Medium | Open ↗ | — | |
| Find The City With The Smallest Number Of Neighbors At A Threshold Distance | Medium | Open ↗ | — | |
| Time Needed To Inform All Employees | Medium | Open ↗ | — |
BIT MANIPULATION
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| A Summary%3A How To Use Bit Manipulation To Solve Problems Easily And Efficiently | Medium | Open ↗ | — |
2- Representation of Linked List
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| 3- https://leetcode.com/problems/delete-node-in-a-linked-list/ | Medium | Open ↗ |
4- Arrays vs Linked List
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7- Doubly Linked List and STLs
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| 8- https://leetcode.com/problems/design-hashset/ | Medium | Open ↗ | ||
| 9- https://leetcode.com/problems/design-hashmap/ | Medium | Open ↗ | ||
| 10- https://leetcode.com/problems/reverse-linked-list/ | Medium | Open ↗ | ||
| 11- Reverse Nodes in k-Group [ https://leetcode.com/problems/reverse-nodes-in-k-group/ ] | Medium | Open ↗ |
12- Reverse Nodes in k-Group (NO EXTRA SPACE)
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| 13- https://leetcode.com/problems/merge-two-sorted-lists/ | Medium | Open ↗ | ||
| 14- https://leetcode.com/problems/merge-k-sorted-lists/ | Medium | Open ↗ | ||
| 15- https://leetcode.com/problems/remove-duplicates-from-sorted-list/ | Medium | Open ↗ | ||
| 16- https://leetcode.com/problems/linked-list-cycle/ | Medium | Open ↗ | ||
| 17- https://leetcode.com/problems/linked-list-cycle-ii/ | Medium | Open ↗ | ||
| 18- https://leetcode.com/problems/intersection-of-two-linked-lists/ | Medium | Open ↗ | ||
| 19- https://leetcode.com/problems/palindrome-linked-list/ | Medium | Open ↗ | ||
| 20- https://leetcode.com/problems/remove-linked-list-elements/ | Medium | Open ↗ | ||
| 21- https://leetcode.com/problems/design-browser-history/ | Medium | Open ↗ |
22- https://leetcode.com/problems/lru-cache/
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| 23- Copy List with Random Pointer ( with extra space ) [ https://leetcode.com/problems/copy-list-with-random-pointer/ ] | Medium | Open ↗ |
HEAP
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| Done | Problem | Level | Practice | Video |
|---|---|---|---|---|
| K Closest Points To Origin | Medium | Open ↗ | — | |
| Kth Largest Element In An Array | Medium | Open ↗ | — | |
| Reorganize String | Medium | Open ↗ | — | |
| Furthest Building You Can Reach | Medium | Open ↗ | — | |
| Kth Smallest Element In A Sorted Matrix | Medium | Open ↗ | — | |
| Cheapest Flights Within K Stops | Medium | Open ↗ | — | |
| Find The Most Competitive Subsequence | Medium | Open ↗ | — | |
| Ugly Number Ii | Medium | Open ↗ | — | |
| Merge K Sorted Lists | Hard | Open ↗ | ||
| Sliding Window Maximum | Hard | Open ↗ | — | |
| The Skyline Problem | Hard | Open ↗ | — | |
| Trapping Rain Water Ii | Hard | Open ↗ | — | |
| Minimum Number Of Refueling Stops | Hard | Open ↗ | — | |
| Swim In Rising Water | Hard | Open ↗ | — | |
| Shortest Path To Get All Keys | Hard | Open ↗ | — | |
| Minimum Cost To Hire K Workers | Hard | Open ↗ | — | |
| K Th Smallest Prime Fraction | Hard | Open ↗ | — |