Sai Vignesh Golla

Solutions, approaches, and the notes I revise from.

Every LeetCode and HackerRank problem I have worked through, read straight out of the source files in the repo at build time. The write-up cannot drift away from the code, because the code is the write-up.

Interview notes Repository

149
Problems: 242
Solutions: 4
Languages: 38
Easy: 90
Medium: 21
Hard

All problems

149 problems

#217Contains DuplicateArrays and HashingPythonJavaEasy
#242Valid AnagramArrays and HashingPythonJavaEasy
#1Two SumArrays and HashingPythonJavaEasy
#49Group AnagramsArrays and HashingPythonJavaMedium
#347Top K Frequent ElementsArrays and HashingPythonJavaMedium
#238Product of Array Except SelfArrays and HashingPythonJavaMedium
#36Valid SudokuArrays and HashingPythonJavaMedium
#128Longest Consecutive SequenceArrays and HashingPythonJavaMedium
#125Valid PalindromeTwo PointersPythonJavaEasy
#167Two Sum II - Input Array Is SortedTwo PointersPythonJavaMedium
#153SumTwo PointersPythonJavaMedium
#42Trapping Rain WaterTwo PointersPythonHard
#567Permutation in StringSliding WindowPythonMedium
#76Minimum Window SubstringSliding WindowPythonJavaHard
#239Sliding Window MaximumSliding WindowPythonHard
#20Valid ParenthesesStackPythonJavaEasy
#155Min StackStackPythonJavaMedium
#150Evaluate Reverse Polish NotationStackPythonMedium
#739Daily TemperaturesStackPythonMedium
#853Car FleetStackPythonMedium
#84Largest Rectangle in HistogramStackPythonHard
#704Binary SearchBinary SearchPythonEasy
#74Search a 2D MatrixBinary SearchPythonMedium
#875Koko Eating BananasBinary SearchPythonMedium
#981Time Based Key-Value StoreBinary SearchPythonMedium
#206Reverse Linked ListLinked ListPythonJavaEasy
#21Merge Two Sorted ListsLinked ListPythonJavaEasy
#141Linked List CycleLinked ListPythonJavaJavaScriptTypeScriptEasy
#143Reorder ListLinked ListPythonJavaMedium
#19Remove Nth Node From End of ListLinked ListPythonJavaMedium
#138Copy List with Random PointerLinked ListPythonMedium
#2Add Two NumbersLinked ListPythonMedium
#287Find the Duplicate NumberLinked ListPythonMedium
#146LRU CacheLinked ListPythonMedium
#23Merge k Sorted ListsLinked ListPythonJavaHard
#25Reverse Nodes in k-GroupLinked ListPythonHard
#104Maximum Depth of Binary TreeTreesPythonJavaJavaScriptTypeScriptEasy
#543Diameter of Binary TreeTreesPythonEasy
#110Balanced Binary TreeTreesPythonEasy
#100Same TreeTreesPythonJavaEasy
#572Subtree of Another TreeTreesPythonJavaEasy
#235Lowest Common Ancestor of a Binary Search TreeTreesPythonJavaMedium
#236Lowest Common Ancestor of a Binary TreeTreesPythonMedium
#102Binary Tree Level Order TraversalTreesPythonMedium
#199Binary Tree Right Side ViewTreesPythonMedium
#1448Count Good Nodes in Binary TreeTreesPythonMedium
#98Validate Binary Search TreeTreesPythonJavaMedium
#230Kth Smallest Element in a BSTTreesPythonJavaMedium
#105Construct Binary Tree from Preorder and Inorder TraversalTreesPythonJavaMedium
#124Binary Tree Maximum Path SumTreesPythonJavaHard
#297Serialize and Deserialize Binary TreeTreesPythonHard
#703Kth Largest Element in a StreamHeap / Priority QueuePythonEasy
#1046Last Stone WeightHeap / Priority QueuePythonEasy
#973K Closest Points to OriginHeap / Priority QueuePythonMedium
#215Kth Largest Element in an ArrayHeap / Priority QueuePythonMedium
#355Design TwitterHeap / Priority QueuePythonMedium
#295Find Median from Data StreamHeap / Priority QueuePythonHard
#212Word Search IITriesPythonJavaHard
#695Max Area of IslandGraphsPythonMedium
#994Rotting OrangesGraphsPythonMedium
#417Pacific Atlantic Water FlowGraphsPythonMedium
#207Course ScheduleGraphsPythonMedium
#261Graph Valid TreeGraphsPythonMedium
#323Number of Connected Components in an Undirected GraphGraphsPythonMedium
#269Alien DictionaryAdvanced GraphsPythonHard
#70Climbing Stairs1-D Dynamic ProgrammingPythonEasy
#198House Robber1-D Dynamic ProgrammingPythonMedium
#213House Robber II1-D Dynamic ProgrammingPythonMedium
#5Longest Palindromic Substring1-D Dynamic ProgrammingPythonMedium
#647Palindromic Substrings1-D Dynamic ProgrammingPythonMedium
#91Decode Ways1-D Dynamic ProgrammingPythonMedium
#322Coin Change1-D Dynamic ProgrammingPythonMedium
#152Maximum Product Subarray1-D Dynamic ProgrammingPythonMedium
#139Word Break1-D Dynamic ProgrammingPythonMedium
#300Longest Increasing Subsequence1-D Dynamic ProgrammingPythonMedium
#62Unique Paths2-D Dynamic ProgrammingPythonJavaMedium
#1143Longest Common Subsequence2-D Dynamic ProgrammingPythonMedium
#39Combination SumBacktrackingPythonMedium
#79Word SearchBacktrackingPythonMedium
#78SubsetsBacktrackingPythonJavaMedium
#53Maximum SubarrayGreedyPythonMedium
#55Jump GameGreedyPythonMedium
#251Meeting RoomsIntervalsPythonEasy
#48Rotate ImageMath and GeometryPythonMedium
#50Pow(x, n)Math and GeometryPythonMedium
#3365Rearrange K Substrings to Form Target StringExtra ProblemsPythonMedium
#3366Minimum Array SumExtra ProblemsPythonMedium
#460LFU CacheExtra ProblemsPythonHard
#1604Alert Using Same Key-Card Three or More Times in a One Hour PeriodExtra ProblemsPythonMedium
#743Network Delay TimeExtra ProblemsPythonMedium
#1975Maximum Matrix SumDaily ChallengesPythonMedium
#1161Maximum Level Sum of a Binary TreeDaily ChallengesPythonMedium
#1339Maximum Product of Splitted Binary TreeDaily ChallengesPythonMedium
#1458Max Dot Product of Two SubsequencesDaily ChallengesPythonHard
#865Smallest Subtree with all the Deepest NodesDaily ChallengesPythonMedium
#712Minimum ASCII Delete Sum for Two StringsDaily ChallengesPythonMedium
#85Maximal RectangleDaily ChallengesPythonMedium
#1266Minimum Time Visiting All PointsDaily ChallengesPythonEasy
#3453Separate Squares IDaily ChallengesPythonMedium
#3454Separate Squares IIDaily ChallengesPythonHard
#2943Maximize Area of Square Hole in GridDaily ChallengesPythonMedium
#2975Maximum Square Area by Removing Fences From a FieldDaily ChallengesPythonMedium
#3047Find the Largest Area of Square Inside Two RectanglesDaily ChallengesPythonMedium
#1895Largest Magic SquareDaily ChallengesPythonMedium
#1292Maximum Side Length of a Square with Sum Less than or Equal to ThresholdDaily ChallengesPythonMedium
#3314Construct the Minimum Bitwise Array IDaily ChallengesPythonEasy
#3315Construct the Minimum Bitwise Array IIDaily ChallengesPythonMedium
#3507Minimum Pair Removal to Sort Array IDaily ChallengesPythonEasy
#3510Minimum Pair Removal to Sort Array IIDaily ChallengesPythonHard
#1877Minimize Maximum Pair Sum in ArrayDaily ChallengesPythonMedium
#1984Minimum Difference Between Highest and Lowest of K ScoresDaily ChallengesPythonEasy
#1200Minimum Absolute DifferenceDaily ChallengesPythonEasy
#3650Minimum Cost Path with Edge ReversalsDaily ChallengesPythonMedium
#3651Minimum Cost Path with TeleportationsDaily ChallengesPythonHard
#2976Minimum Cost to Convert String IDaily ChallengesPythonMedium
#2977Minimum Cost to Convert String IIDaily ChallengesPythonHard
#744Find Smallest Letter Greater Than TargetDaily ChallengesPythonEasy
#3010Divide an Array Into Subarrays With Minimum Cost IDaily ChallengesPythonEasy
#3013Divide an Array Into Subarrays With Minimum Cost IIDaily ChallengesPythonHard
#3637Trionic Array IDaily ChallengesPythonEasy
#3379Transformed ArrayDaily ChallengesPythonEasy
#1382Balance a Binary Search TreeDaily ChallengesPythonMedium
#3719Longest Balanced Subarray IDaily ChallengesPythonMedium
#3721Longest Balanced Subarray IIDaily ChallengesPythonHard
#799Champagne TowerDaily ChallengesPythonMedium
#67Add BinaryDaily ChallengesPythonEasy
#190Reverse BitsDaily ChallengesPythonEasy
#693Binary Number with Alternating BitsDaily ChallengesPythonEasy
#696Count Binary SubstringsDaily ChallengesPythonEasy
#762Prime Number of Set Bits in Binary RepresentationDaily ChallengesPythonEasy
#868Binary GapDaily ChallengesPythonEasy
#1022Sum of Root To Leaf Binary NumbersDaily ChallengesPythonEasy
#1689Partitioning Into Minimum Number Of Deci-Binary NumbersDaily ChallengesPythonMedium
#11Container With Most WaterTwo PointersJavaMedium
#121Best Time to Buy and Sell StockSliding WindowJavaEasy
#3Longest Substring Without Repeating CharactersSliding WindowJavaMedium
#424Longest Repeating Character ReplacementSliding WindowJavaJavaScriptMedium
#153Find Minimum in Rotated Sorted ArrayBinary SearchJavaMedium
#33Search in Rotated Sorted ArrayBinary SearchJavaMedium
#226Invert Binary TreeTreesJavaJavaScriptTypeScriptEasy
#208Implement Trie (Prefix Tree)TriesJavaMedium
#200Number of IslandsGraphsJavaMedium
HRTree: Height of a Binary TreeTreesPythonEasy
HRTree: Level Order TraversalTreesPythonEasy
HRSwap Nodes [Algo]TreesPythonMedium
HRBalanced BracketsStackPythonMedium
HRContactsTriesPythonMedium
HRFind the Running MedianHeap / Priority QueuePythonHard
HRBFS: Shortest Reach in a GraphGraphsPythonHard