Problem Solutions Repository

This repository contains solutions to various algorithmic problems, organized by categories such as arrays, backtracking, binary search, graphs, and more. Each problem is solved in Kotlin, and the solutions are structured in a way that makes it easy to navigate and understand.

Purpose

The purpose of this repository is to provide a comprehensive collection of algorithmic problem solutions that can be used for learning, reference, or interview preparation. The problems are categorized by topic, and each solution is implemented in Kotlin.

How to Generate an Updated File List

To generate an updated list of all files in this repository, you can use the following shell command:

find . -type f | sort > all_problems.txt

This command will recursively find all files in the repository, sort them, and save the list to a file named all_problems.txt.

Repository Structure

Below is a tree-like structure of the repository with links to the files:

.
├── array
│   ├── Combinatorics
│   │   ├── Combinations.kt
│   │   ├── NextPermutation.kt
│   │   ├── Permutation_II.kt
│   │   ├── Permutation_II_Backtracking.kt
│   │   ├── Permutations.kt
│   │   └── Subsets.kt
│   ├── DiagonalTraverse.kt
│   ├── MergeIntervals.kt
│   ├── MergeSortedArray.kt
│   ├── MissingRanges.kt
│   ├── MoveZeroes.kt
│   ├── RemoveElement.kt
│   ├── RotateImage.kt
│   ├── ShortestPathInBinaryMatrix.kt
│   ├── SpiralMatrix.kt
│   ├── ToeplitzMatrix.kt
│   ├── TransposeMatrix.kt
│   ├── backtracking
│   │   ├── CombinationSum.kt
│   │   ├── CombinationSum3.kt
│   │   └── CombinationSum_II.kt
│   ├── dfs
│   │   └── NestedListWeightedSum.kt
│   ├── dp
│   │   ├── CoinChange.kt
│   │   ├── CoinChange_II.kt
│   │   ├── CoinChange_II_BottomUp.kt
│   │   ├── HouseRobber.kt
│   │   ├── HouseRobber_II.kt
│   │   ├── LongestCommonSubarray.kt
│   │   ├── LongestIncreasingSubsequence.kt
│   │   ├── MaximumSumSubArray.kt
│   │   ├── MinCostClimbingStaris.kt
│   │   └── TargetSum.kt
│   ├── greedy
│   │   ├── CanPlaceFlowers.kt
│   │   ├── ContainerWithMostWater.kt
│   │   ├── IncreasingTripletSequence.kt
│   │   ├── KItemsWithMaximumSum.kt
│   │   ├── MaximumDistanceInArray.kt
│   │   ├── MaximumSwap.kt
│   │   ├── MergeOverlappingIntervals.kt
│   │   └── NonOverlappingIntervals.kt
│   ├── hashtable
│   │   ├── EqualRowAndColumnPairs.kt
│   │   ├── FindDifferenceOfTwoArrays.kt
│   │   ├── FindMissingPositive.kt
│   │   ├── LongestConsecutiveSequence.kt
│   │   ├── MaxNUmWithKSumPairs.kt
│   │   ├── RankTransformOfAnArray.kt
│   │   ├── UniqueNumberOfOccurences.kt
│   │   └── ValidSudoku.kt
│   ├── prefixsum
│   │   ├── ContiguousArray.kt
│   │   ├── ContinuousSubarraySum.kt
│   │   ├── FIndTheHighestAltitute.kt
│   │   ├── FindPivotIndex.kt
│   │   ├── Minimum NumberofOperationstoMoveAllBallstoEachBox.kt
│   │   ├── NumberOfZeroFilledSubArrays.kt
│   │   ├── SubArraySumEqualsToK.kt
│   │   └── SubArraySumsDivisibleByK.kt
│   ├── random
│   │   └── RandomPickIndex.kt
│   ├── sorting
│   │   └── SortColors.kt
│   └── twopointer
│       ├── IntervalListIntersection.kt
│       ├── RemoveDuplicateElementsFromSortedArray.kt
│       ├── RemoveDuplicateElementsFromSortedArray_II.kt
│       ├── RotateArray.kt
│       ├── ThreeSum.kt
│       ├── TrappingRainWater.kt
│       └── TwoSum_II.kt
├── autopilot
│   └── H1bAutoPilotStressAnxietyAlgorithm.kt
├── backtracking
│   ├── ExpressionAndAddOperators.kt
│   ├── ExpressionAndAddOperatorsOptimized.kt
│   ├── NQueen.kt
│   └── NQueen_II.kt
├── binarysearch
│   ├── ApartmentHunting.kt
│   ├── CapacityToShipPackageWithinDDays.kt
│   ├── FindFirstAndLastPosition.kt
│   ├── FindKClosestElements.kt
│   ├── FindPeakElement.kt
│   ├── FindPeakElementBetterSolution.kt
│   ├── FirstBadVersion.kt
│   ├── GuessNumberHigherOrLower.kt
│   ├── KThMissingPositiveNumber.kt
│   ├── KokoEatingBanana.kt
│   ├── MedianOfTwoSortedARrays.kt
│   ├── RandomPickWithWeight.kt
│   ├── SearchInRotatedArray_II.kt
│   ├── SearchInRotatedSortedArray.kt
│   ├── SearchInsertionPosition.kt
│   └── ValleyElement.kt
├── bitset
│   ├── FirstLetterToAppearTwice.kt
│   ├── MaximumXorOfTwoNumsInArray.kt
│   ├── NumberOfOneBits.kt
│   └── SingleNumber3.kt
├── cache
│   ├── LFUCache.kt
│   ├── LRUCache.kt
│   └── LRUCacheLinkedList.kt
├── commons
│   ├── APIEndPoints.kt
│   ├── AlpacaWebSocketFactory.kt
│   └── FileWriter.kt
├── disjointset
│   ├── AccountMerge.kt
│   └── UnionFind.kt
├── facebook
│   ├── FindMinimumTicketPrice.kt
│   └── SecondGreatestNumber.kt
├── graph
│   ├── CloneGraph.kt
│   ├── DiameterOfBinaryTree.kt
│   ├── HouseRobber3.kt
│   ├── articulation_point
│   │   ├── CriticalConnectionsInANetwork.kt
│   │   └── FindArticulationPoints.kt
│   ├── bst
│   │   ├── BinarySearchTreeToGreaterSumTree.kt
│   │   └── RangeSumOfBST.kt
│   ├── cycle
│   │   ├── CourseSchedule.kt
│   │   └── CourseSchedule_II.kt
│   ├── dp
│   │   └── CheapestFlightsWithinKStops.kt
│   ├── greedy
│   │   ├── CheapestFlightWithKStops.kt
│   │   ├── CheapestFlightsWithKStops.kt
│   │   └── DonaldTrumpAlgorithm.kt
│   ├── mst
│   │   └── PrimsAlgorithm.kt
│   └── topological_sort
│       ├── AlienDictionary.kt
│       ├── CourseSchedule_II.kt
│       └── CourseSchedule_II_BFS.kt
├── greedy
│   ├── CarFleet.kt
│   ├── JumpGame.kt
│   ├── JumpGame_II.kt
│   ├── MInimumCostHomecomingOfARobot.kt
│   ├── MeetingRooms.kt
│   └── MeetingRooms_II.kt
├── grid
│   ├── MakingALargeIsland.kt
│   ├── MaxAreaOfIsland.kt
│   ├── PacificAtlanticWaterFlow.kt
│   ├── RottingOranges.kt
│   ├── ShortestBridge.kt
│   ├── dynamic_programming
│   │   ├── CherryPickup.kt
│   │   ├── Test.kt
│   │   ├── UniquePaths_I.kt
│   │   └── UniquePaths_II.kt
│   ├── histogram
│   │   └── MaximalRectangle.kt
│   └── search
│       └── WordSearch_II.kt
├── hashtable
│   ├── IntegerToRoman.kt
│   ├── RomanToInteger.kt
│   └── WorlBreak_I_DP.kt
├── heap
│   ├── DualBalancedHeap.kt
│   ├── FindKClosestElements.kt
│   ├── FindScoreOfAnArrayAfterMarkingAllElements.kt
│   ├── MedianFromRunningStream.kt
│   ├── SlidingWindowMedian.kt
│   └── TopKFrequentElements.kt
├── linkedlist
│   ├── AddTwoNumbers.kt
│   ├── CopyLinkedListWithRandomPointer.kt
│   ├── DeleteMiddleNodeOfLinkedList.kt
│   ├── InsertIntoASortedCircularLinkedList.kt
│   ├── LinkedListCycle.kt
│   ├── MergeKSortedList.kt
│   ├── MergeKSortedListIterative.kt
│   ├── MergeTwoSortedLIst.kt
│   ├── OddEvenLinkedList.kt
│   ├── OddOrEvenLinkedList.kt
│   ├── RemoveNthNodeFromEndOfList.kt
│   ├── ReverseLinkedList.kt
│   └── ReverseNodesInKGroups.kt
├── math
│   ├── AddStrings.kt
│   ├── DetectSquares.kt
│   ├── MultiplyStrings.kt
│   ├── ReverseInteger.kt
│   ├── StringtoIntegerAtoi.kt
│   ├── geometry
│   │   └── ErectTheFence_ConvexHull.kt
│   ├── pow.kt
│   └── stack
│       ├── BasicCalculator.kt
│       ├── BasicCalculator_I.kt
│       ├── BasicCalculator_II.kt
│       └── BasicCalculator_II_ShortCode.kt
├── microsoft
│   ├── Demo.kt
│   ├── NonNegativeSum.java
│   ├── Toast.kt
│   └── ValidTime.kt
├── ml
│   └── classical
│       └── tree
│           └── core
│               └── DecisionTree.kt
├── numbers
│   └── PalindromeNumber.kt
├── probability
│   ├── InsertDeleteGetRandomAtO1.kt
│   ├── LinkedListRandomNode.kt
│   └── ReservoirSampling.kt
├── queueu
│   └── dequeue
│       └── NumberOfRecentCalls.kt
├── quicksort
│   ├── KClosestPointsToOrigin.kt
│   ├── KThLargestElementInArray.kt
│   └── TopKFrequentElements.kt
├── real_word_projects
│   ├── HttpApiCall.kt
│   ├── InterfaceExample.kt
│   ├── ParallelFibonacci.kt
│   ├── SystemInterviewHack.kt
│   ├── TradingAPICallExample.kt
│   ├── database
│   │   └── AiTest.kt
│   ├── dynamic_programming
│   │   └── DuckworthLewisStern.kt
│   ├── json
│   │   └── JsonExample.kt
│   ├── parallel_algorithms
│   │   ├── FindMaxInArray.kt
│   │   └── ParallelMatrixMultiplication.kt
│   └── trading
│       ├── AlpacaSDKExamples.kt
│       ├── RealtimeMarketDataStreaming.kt
│       ├── system_design_plantuml.txt
│       └── trading_data.json
├── simulation
│   ├── CountCollisionsOnARoad.kt
│   ├── Racecar.kt
│   └── TextJustification.kt
├── sliding_window
│   ├── LongestSubArraysOfOneAfterDeletingOneElement.kt
│   ├── LongestSubstringWithoutRepeatingCharacter.kt
│   ├── MaxConsecutiveOnes_III.kt
│   ├── MaximumAverageSubarray_I.kt
│   ├── MaximumErasureValue.kt
│   ├── MaximumSumOfDistinctSubarraysWithLengthK.kt
│   ├── MinimumSizeSubarraySum.kt
│   ├── PartitionLabels.kt
│   └── SlidingWindowMaximum.kt
├── speed_dating
│   └── ComputerScienceEngineerDating.kt
├── stack
│   ├── AestroidCollisions.kt
│   ├── BuildingsWithAnOceanView.kt
│   ├── DailyTemperatures.kt
│   ├── EvaluateReversePolishNotation.kt
│   ├── LargestRectangleInHistogram.kt
│   ├── MinimumAddtoMakeParenthesesValid.kt
│   ├── MinimumRemoveToMakeValidParentheses.kt
│   ├── NextGreaterElement_I.kt
│   ├── OnlineStockSpan.kt
│   ├── RemoveStarsFromString.kt
│   └── ValidParentheses.kt
├── stock_market
│   ├── dp
│   │   ├── BestTimeToBuyAndSellStock.kt
│   │   ├── BestTimeToBuyAndSellStockWithCooldown.kt
│   │   ├── BestTimeToBuyAndSellStockWithTransactionFee.kt
│   │   └── BestTimeToBuyAndSellStock_III.kt
│   └── greedy
│       └── BestTimeToBuyAndSellStock_II.kt
├── stream
│   └── MovingAverageOfARunningStream.kt
├── string
│   ├── CountAndSay.kt
│   ├── CountWordsWithAGivenPrefix.kt
│   ├── GoatLatin.kt
│   ├── GreatestCommonDivisorOfStrings.kt
│   ├── IsSubsequence.kt
│   ├── MaximumValueOfAStringIsAnArray.kt
│   ├── MergeStringAlternatively.kt
│   ├── ReverseVowelOfString.kt
│   ├── ReverseWordsInString.kt
│   ├── StringCompression.kt
│   ├── ValidNumber.kt
│   ├── ValidPalindrome.kt
│   ├── ValidPalindrome_II.kt
│   ├── ValidWordAbbreviation.kt
│   ├── backtracking
│   │   └── GenerateParantheses.kt
│   ├── dynamic_programming
│   │   ├── EditDistance.kt
│   │   ├── LongestCommonSubsequence.kt
│   │   ├── LongestCommonSubstring.kt
│   │   ├── RegularExpressionMatching.kt
│   │   └── ValidPalindrome_III.kt
│   ├── hashtable
│   │   ├── DetermineIfStringsAreClose.kt
│   │   ├── GroupShiftedStrings.kt
│   │   └── UniqueLength3PalindromicSubsequence.kt
│   ├── pattern_matching
│   │   └── FindTheIndexofTheFirstOccurrenceIna String.kt
│   ├── sliding_window
│   │   ├── MaximumNumberofVowelsinSubstringofGivenLength.kt
│   │   └── MinimumWindowSubstring.kt
│   └── stack
│       ├── DecodeString.kt
│       ├── RemoveAllAdjacentDuplicatesInString.kt
│       └── SimplifyPath.kt
├── trading
│   └── trading_data.json
├── tree
│   ├── AllNodesDistanceKinBinaryTree.kt
│   ├── BinaryTreeLevelOrderTraversal.kt
│   ├── BinaryTreeRightSideView.kt
│   ├── BinaryTreeVerticalOrderTraversal.kt
│   ├── BinaryTreeVerticalOrderTraversal_WithoutSorting.kt
│   ├── BinaryTreeZigZagLevelOrderTraversal.kt
│   ├── BoundaryOfBinaryTree.kt
│   ├── ConstructBinaryTreeFromPreorderAndInOrderTraversal.kt
│   ├── ConstructBinaryTreeFromString.kt
│   ├── CountGoodNodeInBInaryTree.kt
│   ├── CountNodeEqualsAverage.kt
│   ├── LeafSimilar.kt
│   ├── LowestCommonAncestor.kt
│   ├── LowestCommonAncestor_III.kt
│   ├── MaximumDepthOfBinaryTree.kt
│   ├── MaximumSumBSTInBinaryTree.kt
│   ├── MaximumWidthOfBinaryTree.kt
│   ├── MinimumTimeToCollectAllApplesInATree.kt
│   ├── PathSum.kt
│   ├── PathSumIII.kt
│   ├── PathSum_II.kt
│   ├── PopulatingNextRightPointerInEachNode.kt
│   ├── StepByStepDirectionsFromANodeToAnother.kt
│   ├── bfs
│   │   ├── AverageOfLevelsInBinaryTree.kt
│   │   ├── BinaryTreeLevelOrderTraversal_II.kt
│   │   ├── CheckCompletenessOfBinaryTree.kt
│   │   └── FindLargestValueInEachTreeRow.kt
│   ├── bst
│   │   ├── BSTIterator.kt
│   │   ├── ClosestBinarySearchTreeValue.kt
│   │   ├── ConvertBInarySearchTreeToSortedDoublyLinkedList.kt
│   │   ├── DeleteNodeinABST.kt
│   │   ├── LongestIncreasingSubsequence.kt
│   │   └── SkylineProblem.kt
│   └── mst
│       ├── MinCostToConnectAllPointsKruskal.kt
│       └── MinCostToConnectAllPointsPrims.kt
└── trie
    ├── AutoCompleteSystem.kt
    ├── AutoCompleteSystemWithHeap.kt
    ├── EqualRowAndColumnPairs.kt
    ├── LongestCommonPrefix.kt
    ├── SearchSuggestionSystem.kt
    └── WordBreak_I.kt

Contributing

If you would like to contribute to this repository, feel free to submit a pull request. Please ensure that your solutions are well-documented and follow the existing structure.

License

This repository is licensed under the MIT License. See the LICENSE file for more details.

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Happy coding! 🚀