Coding & Algorithms
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Arrays & Strings0 / 109
- Manually Parse a Bounded IntegerAmazonMedium
- Generate the nth Run-Count Sequence TermGoogleMedium
- Find the First Absent Positive IntegerAmazonHard
- Return a Longest Palindromic SliceAmazonMedium
- Validate a Signed Decimal and Exponent SpellingGoogleHard
- Read a Down-and-Up Character Layout by RowGoogleMedium
- Find the Shared Starting StringGoogleEasy
- Advance an Array to Its Next Lexicographic OrderAmazonMedium
- Measure the Final Word Before Trailing SpacesGoogleEasy
- Justify Greedy Lines to an Exact WidthGoogleHard
- Reverse Word Order and Normalize ASCII SpacesGoogleMedium
- Compare Dotted Revision Values with Missing ZerosGoogleMedium
- Recover a Guaranteed More-Than-Half MajorityGoogleEasy
- Rotate the Original Array Right by a Nonnegative CountGoogleMedium
- Build the Shortest Palindrome by Prepending OnlyGoogleHard
- Find Values Occurring More than One Third of the ArrayAmazonMedium
- Measure the Closest Occurrences of Two Different WordsSnowflakeEasy
- Recognize the Three Valid Capitalization PatternsGoogleEasy
- Reverse the First Part of Each Two-Block String ChunkGoogleEasy
- Reverse Characters Inside Each Sentence WordMicrosoftEasy
- Check a Robot's Final DisplacementBloombergEasy
- Find the Fewest Repetitions Containing a Target StringAmazonMedium
- Count Equal-Size Adjacent Binary RunsDeshawEasy
- Convert Uppercase ASCII LettersGoogleEasy
- Find the First Position with Balanced Side SumsAmazonEasy
- Check Whether the Maximum Dominates Every Other ValueGoogleEasy
- Recognize a Cyclic Left ShiftGoogleEasy
- Apply Matching String Replacements SimultaneouslyGoogleMedium
- Match Two Strings with Exactly One Distinct-Index SwapAmazonEasy
- Recognize Nondecreasing or Nonincreasing ArraysGoogleEasy
- Partition an Array into Even Values Followed by Odd ValuesAmazonEasy
- Validate One Strict Rise Followed by One Strict DescentGoogleEasy
- Verify Lexicographic Word Order under a Supplied AlphabetAmazonEasy
- Maximize Two Sight Values Minus Their Index DistanceGoogleMedium
- Duplicate Zeros Within a Fixed ArrayGoogleEasy
- Bracket the Dots in an IPv4 AddressGoogleEasy
- Array After Simultaneous Local-Extremum UpdatesVirtu FinancialEasy
- Replace Each Value by Its Original Suffix MaximumGoogleEasy
- Longest Proper Prefix That Is Also a SuffixGoogleHard
- Could Each Child Have the Most Candies?GoogleEasy
- Largest Product After Decrementing Two Distinct EntriesGoogleEasy
- Interleave Two Equal-Length Array HalvesGoogleEasy
- Inclusive Running Sums of an Integer ArrayGoogleEasy
- Move Each Character to Its Specified Destination IndexMicrosoftEasy
- First Champion to Win k Consecutive Array ComparisonsGoldman SachsMedium
- Detect an Odd Run of Length ThreeMicrosoftEasy
- Replace Circular Entries with Neighbor SumsAmazonEasy
- Count Deletions that Balance Index-Parity SumsGoDaddyMedium
- Equalize All Mirrored Pair SumsAmazonMedium
- Find the Highest Point from Altitude ChangesGoogleEasy
- Find the Largest Magnitude of a Subarray SumGoogleMedium
- Recognize a Rotation of Nondecreasing ValuesGoogleEasy
- List Buildings That Clear Every Building to Their RightMetaMedium
- Interleave Two Words Starting with the FirstGoogleEasy
- Find the Second-Greatest Distinct DigitMetaEasy
- Find the Longest Ordered Run Containing Every VowelRipplingMedium
- Count Three-Character Windows Without RepetitionAmazonEasy
- Largest Odd Slice of a Decimal StringAmazonEasy
- Can One Removal Restore Strict Order?AppianEasy
- Erase the Earliest Matching Block RepeatedlyGoogleMedium
- Compose a Zero-Based Permutation with ItselfAmazonEasy
- Append a Second Copy of an ArrayGoogleEasy
- Count Matching Pattern EntriesGoogleEasy
- Reverse Through the First Matching CharacterAmazonEasy
- Evaluate Increment and Decrement CommandsGoogleEasy
- Count All-Vowel Substrings Containing Every VowelDeshawEasy
- Remove Both Extremes by Trimming EndsBloombergMedium
- Most Words in One SentenceAmazonEasy
- Stable Alternation of Positive and Negative EntriesAmazonMedium
- Stable Three-Way Partition Around a PivotAmazonMedium
- Reduce Consecutive Digit Groups until the String Is Short EnoughCapital OneEasy
- Add Distinct-Letter Counts across Every SubstringAmazonHard
- Return the Greatest Repeated-Digit Triple in a Long NumberGoogleEasy
- Discount Only Complete Dollar-Price Words in a SentenceAmazonMedium
- Solve array duplicate flags and binary swapsSalesforceMedium
- Measure the Longest Substring Advancing One Alphabet Letter at a TimeIBMMedium
- Check equal character frequenciesBloombergMedium
- Find the Largest Positive Value with a Negative CounterpartGoogleEasy
- Expand Each Positive Integer into Its Ordered Decimal DigitsGoogleEasy
- Return Absolute Differences of Strictly Left and Right SumsGoogleEasy
- Count Equal-Colored Neighbors After Each RecoloringCapital OneMedium
- Check an Array Against the Good-Array DefinitionGoogleEasy
- Count Index Pairs with a Sum Below the TargetAmazonEasy
- Maximize the Value of an Ordered Index TripletAmazonMedium
- Shortest Substring with Exactly k Ones and Lexicographic TiesAmazonMedium
- Return Indices of Words Containing a Given CharacterGoogleEasy
- Find All Strict Interior Peak IndicesTCSEasy
- Result of the Prescribed Two-Array DistributionGoogleEasy
- Longest Strictly Monotonic SubarrayYandexEasy
- Score from Adjacent ASCII DifferencesGoogleEasy
- Find a Character in the Growing Alphabet StringAmazonEasy
- Sum Subarrays Defined by Each Ending ValueGoogleEasy
- Largest Value in Exactly One Fixed-Length SubarrayGoogleEasy
- Fully Expand Replacement PlaceholdersGoogleMedium
- Reverse Degree of a Lowercase StringGoogleEasy
- Maximize Active Sections After One TradeGoogleMedium
- Independent Active-Section Trade QueriesGoogleHard
- Smallest Palindromic RearrangementGoogleMedium
- Kth Distinct Palindromic RearrangementMetaHard
- First Index Equal to Its Value's Digit SumGoogleEasy
- Apply Special String CommandsAmazonMedium
- Character After Special String CommandsAmazonHard
- Maximum Total Subarray Range with Repeatable ChoicesTCSMedium
- Count Subarrays with a Target MajorityGoogleMedium
- Find the Longest Non-Decreasing Subarray After One ReplacementGoogleMedium
- Count Target-Majority Subarrays in a Large ArrayAmazonHard
- Zero-Filtered Digit Products for Substring QueriesAmazonMedium
- Weighted Word Mapping in Reverse Alphabet OrderGoogleEasy
- Longest Arithmetic Subarray with One Optional ReplacementAmazonMedium
Hashing0 / 61
- Measure the Longest Consecutive Value Run in Linear TimeGoogleMedium
- Find Distinct Repeated Ten-Base DNA WindowsAmazonMedium
- Check a One-to-One ASCII Character SubstitutionGoogleEasy
- Detect Whether Any Integer Value RepeatsGoogleEasy
- Detect Equal Values within an Index RadiusGoogleEasy
- Group Strings Equivalent under Uniform Alphabet ShiftsGoogleMedium
- Return Distinct Values Shared by Two ArraysGoogleEasy
- Return Shared Array Occurrences with Minimum MultiplicityAmazonEasy
- Count Position Matches and Remaining Digit MatchesGoogleMedium
- Detect a Length-Two-or-More Multiple-Sum SegmentAmazonMedium
- Find the Longest Balanced Binary SegmentGoogleMedium
- Count Distinct Value Pairs with a Fixed GapGoogleMedium
- Find the Longest Subsequence with Exact Value Spread OneAmazonEasy
- Identify the Duplicated and Missing Set ValuesAmazonEasy
- Find the Shortest Segment Preserving Array DegreeGoogleEasy
- Count Case-Sensitive Jewel OccurrencesAmazonEasy
- Count Distinct Concatenated Morse EncodingsGoogleEasy
- Exchange One Box Each to Equalize Two Candy TotalsMicrosoftEasy
- Count Delivery Addresses after Local-Name Dot and Plus RulesMicrosoftEasy
- Count Nonempty Binary Segments with an Exact SumGoogleMedium
- Count Contiguous Segments Whose Sum Is Divisible by KGoogleMedium
- Return the Multiset of Characters Present in Every WordAmazonEasy
- Count Song Pairs Whose Combined Duration Is a Multiple of SixtyAmazonMedium
- Most Widely Shared Three-Visit Website PatternAmazonMedium
- Total Length of Independently Formable WordsGoogleEasy
- Transactions Flagged by Amount or Cross-City TimingBloombergMedium
- How Many Copies of balloon Can Be Assembled?AmazonEasy
- Are All Value Frequencies Different?GoogleEasy
- Longest Ordered Subsequence With a Fixed StepGoogleMedium
- Count Subarrays Containing Exactly k Odd ValuesInMobiMedium
- Fewest Replacements Making One String an AnagramJPMorgan ChaseMedium
- Count Strictly Smaller Array Occurrences for Each ValueAmazonEasy
- Maximum Four-Person Families in a CinemaGoogleMedium
- Terminal City of a Directed Travel LineAmazonEasy
- Count Equal-Value Index PairsGoogleEasy
- Remove the Shortest Block to Restore DivisibilityGoogleMedium
- Compare Strings Under Swaps and Global RenamingGoogleMedium
- Remove as Many Target-Sum Pairs as PossibleGoogleMedium
- Count Words Using Only Permitted LettersGoogleEasy
- Add Values That Occur OnceGoogleEasy
- Sum Frequency Imbalance Across SubstringsBloombergMedium
- Recover Entries from a Shuffled Doubled MultisetGoogleMedium
- Values Appearing Alone Without Consecutive NeighborsAppleMedium
- Distinct Values Exclusive to Each of Two ArraysBloombergEasy
- Players with No Losses or Exactly One LossGoogleMedium
- Count Index Pairs That Disagree with Their Value DifferenceGoogleMedium
- Detect Equal Sums among Different Adjacent PairsGoogleEasy
- Sum Index Distances to Every Equal-Valued OccurrenceBloombergMedium
- Count Values Shared by Both Prefixes at Each PositionGoogleMedium
- Sum Squared Distinct Counts Across All SubarraysGoogleEasy
- Count Array Positions Whose Values Appear in the Other ArrayGoogleEasy
- Find the Repeated and Missing Values in a Square GridGoogleEasy
- Smallest Missing Value at or Above a Sequential Prefix SumGoogleEasy
- Count Occurrences of the Most Frequent ValuesGoogleEasy
- Maximize Boundary-Difference Subarray SumGoogleMedium
- Longest Decimal Prefix Shared Across Two Integer ArraysGoogleMedium
- Shortest Substring of Each String That Appears in No Other StringMoveworksMedium
- Letters Appearing in Both CasesAmazonEasy
- Count Letters with Ordered Lowercase and Uppercase OccurrencesGoogleMedium
- Smallest Absent Positive MultipleBloombergEasy
- Missing Values Inside a Retained RangeGoogleEasy
Two Pointers & Sliding Window0 / 68
- Measure Rainwater Held Between BarsAmazonHard
- Find All Distinct Four-Value Target GroupsGoogleMedium
- Find the Shortest Substring Covering Required CharactersAmazonHard
- Find Every Concatenation Starting IndexGoogleHard
- Measure the Longest Segment of Distinct CharactersGoogleMedium
- Choose Vertical Sides for the Greatest Water CapacityGoogleMedium
- Choose the Closest Three-Position SumGoogleMedium
- Remove Chosen Values from an Array PrefixGoogleEasy
- Compact a Sorted Array into Its Distinct PrefixGoogleEasy
- Keep at Most Two Copies in a Sorted Array PrefixAmazonMedium
- Merge Sorted Values into an Existing Array BufferGoogleEasy
- Compare Normalized ASCII Phrase SymmetryGoogleEasy
- Return the Unique Sorted Target Pair as One-Based IndicesGoogleMedium
- Minimize a Positive-Array Target Window LengthGoogleMedium
- Detect a Bounded-Index Pair with Near-Equal ValuesGoogleHard
- Move Zeros In Place while Preserving Nonzero OrderAmazonEasy
- Find a Repeated Value without Modifying the ArrayGoogleMedium
- Reverse the Original Printable-Character Array In PlaceGoogleEasy
- Reverse Only Vowel Occurrences in an ASCII StringGoogleEasy
- Detect a Permuted Pattern in a Contiguous WindowMetaMedium
- Count Index Triples that Form Nondegenerate TrianglesBloombergMedium
- Maximize the Average of an Exactly K-Length SegmentAmazonEasy
- Count Palindrome Occurrences among Contiguous SubstringsAmazonMedium
- Select the K Closest Sorted Values with Smaller-Value TiesGoogleMedium
- Check for a Palindrome after at Most One DeletionAmazonEasy
- Count Segments with a Small ProductGoogleMedium
- Resolve Simultaneous Left and Right Domino PushesAndurilMedium
- Compare Two Backspace-Edited StringsGoogleEasy
- Find the Longest Strict Rise Followed by a Strict FallTikTokMedium
- Choose an Empty Seat with the Best Nearest-Neighbor DistanceYandexMedium
- Place Even Values at Even Indices and Odd Values at Odd IndicesAmazonEasy
- Check Whether Repeated Keystrokes Can Produce a Typed NameGoogleEasy
- Square a Sorted Array and Return the Squares in OrderBloombergEasy
- Count Contiguous Subarrays with Exactly K Distinct ValuesGoogleHard
- Find the Longest Binary Window Requiring at Most K Zero FlipsAmazonMedium
- Most Satisfied Customers With One Calm WindowAmazonMedium
- Fewest Arbitrary Swaps for One Block of OnesAmazonMedium
- Lexicographically Greatest Contiguous SubstringMicrosoftHard
- Most Frequent Substring Under Distinct-Letter and Length LimitsMicrosoftMedium
- Count Fixed-Length Windows Meeting an Average ThresholdAmazonMedium
- Count Substrings That Include a,b and cGoogleMedium
- Highest Score from Exactly k End CardsAmazonMedium
- Longest Window Whose Largest Pair Difference Meets a LimitGoogleMedium
- Most Vowels in a Fixed-Length SubstringGoogleMedium
- Longest Run of Ones After One Required DeletionAmazonMedium
- Count Subsequences with a Bounded Minimum-Plus-MaximumAmazonMedium
- Largest Forward Path Sum Across Two Increasing ArraysGoogleHard
- Reduce a Target by Removing Array EndsGoogleMedium
- Choose a Highest-Sum Distinct SubarrayGoogleMedium
- Gather K Ones with Adjacent SwapsAmazonHard
- Increase Values to Maximize One FrequencyAmazonMedium
- Fewest Replacements for a Consecutive SetJuspayHard
- Longest Uniform Answer Block After Limited ChangesAmazonMedium
- Group Circular Ones with Arbitrary SwapsAmazonMedium
- Find the Latest Unoccupied Arrival Time That Still Boards a BusGoogleMedium
- Can board states be transformed?GoogleMedium
- Count Segments Whose Exact Minimum and Maximum Match Two BoundsPhonePeHard
- Maximize a Fixed-Length Window Sum with No Repeated ValuesGoogleMedium
- Return the Least Value Present in Both Sorted ArraysGoogleEasy
- Return the Negative x-th Order Statistic of Every Fixed WindowInfosysMedium
- Make a Minimum-Change Palindrome with Lexicographic Tie-BreakingIBMEasy
- Count Subarrays Whose Values Stay Within TwoAmazonMedium
- Longest Subarray with Every Value Occurring at Most k TimesAmazonMedium
- Count Subarrays with at Least k Occurrences of the Global MaximumAmazonMedium
- Find Pattern Starts with a Nearby Second PatternPalantirMedium
- Longest Substring with At Most Two of Each CharacterMetaEasy
- Count Alternating Groups around a CircleCapital OneMedium
- Reschedule Meetings for the Longest Free PeriodFivetranMedium
Linked Lists0 / 22
- Reverse Complete Groups of Linked NodesGoogleHard
- Remove a Linked Node by Its Distance from the TailGoogleMedium
- Rotate a List Right by a Large CountAmazonMedium
- Remove Every Repeated-Value Run from a Sorted ListAmazonMedium
- Keep One Representative of Each Sorted List ValueGoogleEasy
- Partition List Nodes Stably around a ThresholdAmazonMedium
- Reverse an Inclusive Segment of List NodesBloombergMedium
- Copy List Nodes with Next and Arbitrary Random LinksAmazonMedium
- Locate a Cycle Entry without Changing the ListAmazonMedium
- Reorder Existing Nodes from Alternating List EndsGoogleMedium
- Remove Every Matching Node from a Linked ChainGoogleEasy
- Reverse Linked-Node Order by Iteration and RecursionGoogleEasy
- Delete a Non-Tail Value through Its Supplied NodeMetaMedium
- Relink Odd Positions before Even Positions StablyAmazonMedium
- Maintain a List with Indexed Insertions and DeletionsGoogleMedium
- Return the Later Middle Node of a Singly Linked ListGoogleEasy
- Read a Binary Integer From Native List NodesAmazonEasy
- Exchange Two Symmetric List ValuesGoogleMedium
- Distances Between Strict Linked-List Turning PointsAmazonMedium
- Reverse Linked-List Groups of Actual Even SizeGoogleMedium
- Unlink the Later Middle NodeGoogleMedium
- Largest Sum of Symmetric List PartnersAmazonMedium
Stacks & Queues0 / 40
- Longest Balanced Parentheses SubstringAmazonHard
- Canonicalize an Absolute Unix PathRobloxMedium
- Find the Largest Rectangle Under Histogram BarsGoogleHard
- Check Matching and Nested BracketsGoogleEasy
- Evaluate Postfix Arithmetic with Truncating Integer DivisionGoogleMedium
- Evaluate Parenthesized Sums with Unary MinusAmazonHard
- Find Each Circular Successor with a Larger ValueAmazonMedium
- Separate Nested Function Calls into Exclusive TimesGoogleMedium
- Apply Score-Record Operations and Sum the Remaining ScoresGoogleEasy
- Aggregate Element Counts in Nested FormulasAgodaHard
- Count Days until a Strictly Warmer ReadingGoogleMedium
- Evaluate Parenthesized Integer ArithmeticGoogleHard
- Count Fleets Reaching a Common DestinationAmazonMedium
- Score a Balanced Parenthesis ExpressionGoogleMedium
- Find the Shortest Contiguous Segment Reaching a Sum ThresholdDevRevHard
- Report Consecutive Historical Price Spans as Quotes ArriveGoogleMedium
- Sum the Minimum Value of Every Contiguous SubarrayAmazonMedium
- Insert the Fewest Parentheses to Make a String BalancedMicrosoftMedium
- Arrange a Deck for Increasing Reveal-and-Rotate OrderGoogleMedium
- Remove One Outer Pair from Every Primitive Parentheses ComponentAmazonEasy
- String Remaining After Equal-Neighbor ErasureGoogleEasy
- Smallest Subsequence Keeping Each Letter OnceGoogleMedium
- Split Parentheses to Minimize the Larger DepthAmazonMedium
- Reverse Every Parenthesized Segment From Inside OutGoogleMedium
- Erase Equal Adjacent Runs of Size kAmazonMedium
- Remove the Fewest Parentheses to Restore ValidityMetaMedium
- Build a Target Stack from an Increasing StreamGoogleMedium
- Compute final prices with next smaller discountUberMedium
- Fewest Insertions When Each Opening Requires a Consecutive Closing PairGoogleMedium
- Remove Adjacent Opposite-Case Copies of the Same LetterGoogleEasy
- Measure the Deepest Parenthesis NestRipplingEasy
- Count Students Left When Lunch Service StopsAmazonEasy
- Count Visible People to the RightGoogleHard
- Seconds Until a Chosen Ticket Buyer FinishesGoogleEasy
- Sum Every Subarray's Maximum-Minus-MinimumAmazonMedium
- Sum Every Segment Minimum Multiplied by Its Segment SumAmazonHard
- Erase Each Star and Its Nearest Remaining Letter to the LeftAmazonMedium
- Print the Smallest String through a Last-In-First-Out Robot BufferBloombergMedium
- Find the Shortest Length After Removing AB and CDMetaEasy
- Maximize Total Height in a Mountain of TowersMicrosoftMedium
Binary Search0 / 30
- Search a Rotated Increasing ArrayAmazonMedium
- First and Last Indices of a ValueGoogleMedium
- Find the Sorted Insertion IndexGoogleEasy
- Return the Floor of a Square RootAmazonEasy
- Search a Matrix with Ordered Row BoundariesGoogleMedium
- Search a Rotated Array that May Repeat ValuesAmazonMedium
- Locate the Middle Value Across Two Sorted InputsGoogleHard
- Return Any Strict Peak Index in Logarithmic TimeGoogleMedium
- Locate a Rotated Minimum despite Duplicate AmbiguityGoogleHard
- Find an Index by Halving a Sorted RangeGoogleEasy
- Find the Next Strictly Larger Letter with WraparoundGoogleEasy
- Place New Stations to Minimize the Widest GapGoogleHard
- Locate a Guaranteed Mountain Peak LogarithmicallyAmazonMedium
- Three Smallest Product Suggestions for Every Typed PrefixAmazonMedium
- Smallest Divisor Meeting a Rounded-Sum LimitMicrosoftMedium
- Earliest Day for m Disjoint Adjacent-Flower BouquetsFlipkartMedium
- Kth Positive Integer Missing from an Increasing ArrayAmazonEasy
- Maximize the Smallest SeparationAmazonMedium
- Split Bags to Minimize the Largest BagAmazonMedium
- Maximize One Value Under a Neighbor-Difference BudgetMicrosoftMedium
- Locate Any Strict Peak in a MatrixAmazonMedium
- Values Safe Under Every Search PivotUberMedium
- Distribute Product Types with the Smallest Store CapGoogleMedium
- Earliest Time to Finish Enough Independent TripsGoogleMedium
- Largest Equal Candy Portion for Every ChildAmazonMedium
- Add Range-Powering Stations to Raise the Weakest CityTeradataHard
- Minimize the Largest Value When Picking at Least k Non-Adjacent HousesMicrosoftMedium
- Find the Earliest Time All Parallel Mechanics FinishGoogleMedium
- Find the First Query Prefix That Can Make an Array ZeroGoogleMedium
- Minimize the Longest Equal-Character SubstringArista NetworksHard
Sorting0 / 32
- Arrange Three Encoded Colors without Library SortingAmazonMedium
- Insert Linked Nodes into a Sorted ChainAmazonMedium
- Sort a Linked Chain with Constant-Workspace Merge PassesGoogleMedium
- Find the Largest Sorted-Neighbor Gap in Linear TimeMetaMedium
- Maximize the Canonical Concatenation of Integer SpellingsAmazonMedium
- Reorder the Original Array into Strict Alternating PeaksIBMMedium
- Count Strictly Smaller Later Occurrences for Every PositionGoogleHard
- Find the Largest Supported Citation ThresholdGoogleMedium
- Count Inclusive-Band Sums of Nonempty Index RangesAmazonHard
- Measure the Smallest Segment that Needs SortingGoogleMedium
- Sort Integers in Ascending Order with Constant Auxiliary StorageGoogleMedium
- Sort a Permutation Using a Bounded Sequence of Prefix ReversalsAmazonMedium
- Count Heights Away From Their Sorted PositionsGoogleEasy
- All Closest Pairs of Distinct Array ValuesAmazonEasy
- Keep Only Folders Without a Listed AncestorAmazonMedium
- Dense Ranks Preserving Value Order and EqualityAmazonEasy
- Order Integers by Set-Bit Count Then ValueGoogleEasy
- Rank Teams from Ballot PreferencesNetappMedium
- Can All Values Be Rearranged into an Arithmetic Progression?GoogleEasy
- Order Integers by Rarity and Descending TiesBloombergEasy
- Buy the Most Bars Using Counting SortAmazonMedium
- Select a Ranked Large Decimal IntegerMetaMedium
- Sorted Positions of a Target ValueGoogleEasy
- Choose a Maximum-Sum Ordered SubsequenceAmazonEasy
- Remove the Fewest Units to Equalize Nonempty BagsDeshawMedium
- Rank Fixed-Width Numeric Suffixes with Original-Index TiesEPAM SystemsMedium
- Order Names by Their Paired Distinct HeightsMicrosoftEasy
- Rank Student Reports by Whole-Word Feedback ScoresBooking.comMedium
- Smallest Array Reachable Through Value-Limited SwapsGoldman SachsMedium
- Build the Result of a Two-Player Minimum-Removal GameAmazonEasy
- Minimum Swaps for Digit-Sum OrderAmazonMedium
- Remove Elements to Balance the Remaining ValuesSalesforceMedium
Trees0 / 82
- Construct Every BST Shape on Consecutive KeysMetaMedium
- Traverse Binary-Tree Values in Left-Root-Right OrderGoogleEasy
- Restore a BST after Two Stored Values Were ExchangedAmazonMedium
- Compare Binary Trees at Matching Structural PositionsAmazonEasy
- Check Reflected Binary-Tree Structure and ValuesAmazonEasy
- Group Binary-Tree Values by Left-to-Right LevelGoogleMedium
- Build a Balanced Tree from an Ascending Linked ListGoogleMedium
- Build Any Balanced BST from a Strictly Increasing ArrayAmazonEasy
- Collect Every Target-Sum Root-to-Leaf Value PathGoogleMedium
- Measure the Longest Root-to-Leaf Node PathGoogleEasy
- Reconstruct a Tree from Preorder and Inorder ValuesGoogleMedium
- Reconstruct a Tree from Inorder and Postorder ValuesGoogleMedium
- Test Height Balance throughout a Binary TreeGoogleEasy
- Measure the Shortest Root-to-Leaf Node PathTCSEasy
- Find Whether a Complete Root Path Has a Target SumGoogleEasy
- Flatten Existing Tree Nodes into a Preorder Right ChainGoogleMedium
- Link Neighbors across Missing Binary-Tree ChildrenAmazonMedium
- Read Binary-Tree Values in Root-Left-Right OrderAmazonEasy
- Count a Complete Binary Tree without Visiting Every NodeGoogleMedium
- Mirror Binary-Tree Child Links through the Original RootGoogleEasy
- List Every Original Root-to-Leaf Value PathBloombergEasy
- Return All Minimum-Height Roots of an Undirected TreeGoogleMedium
- Select a One-Based Inorder Rank in a Search TreeBloombergMedium
- Find Original-Node Common Ancestors in a Search TreeGoogleMedium
- Choose the Closest Search-Tree Value with Smaller-Value TiesRobloxEasy
- Traverse Tree Columns with Stable Row TiesBloombergMedium
- Measure the Smallest Gap Between BST Node ValuesGoogleEasy
- Find the Longest Edge Path in a Binary TreeRobloxEasy
- Measure the Maximum Root-to-Leaf Depth of an N-ary TreeAmazonEasy
- Test for an Exact Descendant Subtree MatchGoogleEasy
- Average Binary-Tree Values at Each DepthAmazonEasy
- Find Two Distinct BST Nodes Summing to a TargetGoogleEasy
- Construct the Unique Maximum-Root Binary TreeGoogleMedium
- Place a Binary Tree in Its Prescribed String GridGoogleMedium
- Measure Binary-Tree Width Including Internal Null GapsAmazonMedium
- Locate a Subtree by Its Search KeyGoogleEasy
- Add a New Key While Preserving Search-Tree OrderGoogleMedium
- Collect Binary-Tree Nodes at an Exact Distance from a TargetAmazonMedium
- Rebuild Any Binary Tree Matching Preorder and PostorderAppleMedium
- Sum Binary-Search-Tree Values inside an Inclusive IntervalGoogleEasy
- Check Whether All Binary-Tree Nodes Carry One ValueAmazonEasy
- Minimize Cameras That Cover a Tree Node and Its NeighborsAmazonHard
- Balance Tree Coins with the Fewest Adjacent TransfersGoogleMedium
- Order Binary-Tree Nodes by Column, Depth and ValueBloombergHard
- Reconstruct the Binary Search Tree Described by PreorderBloombergMedium
- Recover a Binary Tree from Preorder Values with Dash DepthsGrammarlyHard
- Replace Each BST Value with Its Original Greater-or-Equal SumAmazonMedium
- Forest Roots After Removing Selected Tree NodesGoogleMedium
- Can the Second Tree-Coloring Player Force a Majority?AndurilMedium
- Earliest Tree Level With the Largest SumGoogleMedium
- Lowest Region Containing Two Named RegionsAirbnbMedium
- Add Values Whose Grandparent Is EvenAmazonMedium
- Largest Sum of a BST Rooted SubtreeGoogleHard
- Time for News to Reach an Entire Management TreeMicrosoftMedium
- Count Nodes That Match or Exceed Every AncestorJosh TechnologyMedium
- Answer Kth-Ancestor Queries with the Native Tree ClassGoogleHard
- Return the Root Object from Unordered N-ary NodesBloombergMedium
- Count Alternative Insertion Orders for One BSTBloombergHard
- Find the Shared Ancestor Using Parent LinksAppleMedium
- Find an Ancestor Shared by a Node CollectionGoogleMedium
- Graft Small Search Trees into One BSTMicrosoftHard
- Directions Along a Binary Tree PathGoogleMedium
- Build the Unique Binary Tree from Parent DescriptionsAmazonMedium
- Longest Equal-Character Run After Each UpdateGoogleHard
- Count Tree Nodes Matching Their Rounded-Down Subtree AverageSnowflakeMedium
- Measure Infection Time from One Valued Binary-Tree NodeAmazonMedium
- Reverse Stored Values on Each Odd Depth of a Perfect TreeJosh TechnologyMedium
- Choose Alice's Most Profitable Root-to-Leaf Route against BobAmazonMedium
- Count Tree Paths Whose Edge Letters Can Form a PalindromeGoldman SachsHard
- Find Each Node’s Minimum Reversals to Reach the Whole TreeMicrosoftHard
- Sum Squared Distinct Counts Across Large Subarray InputsAmazonHard
- Count Connectable Server Pairs Through Each Tree VertexRipplingMedium
- Highest ID Frequency After Each UpdateSnowflakeMedium
- Container Indices for Longest Shared SuffixesAmazonHard
- Block Placement on a Number LineRobloxHard
- Minimize the Diameter after Joining Two TreesTekionHard
- Maximize Retained Tree Edge Weight with a Degree LimitUberHard
- Place Fruit Types in the Leftmost Eligible BasketsGoogleMedium
- Product Remainder Counts After Array UpdatesGoogleHard
- Odd-Cost Assignments on a Deepest Tree PathAmazonMedium
- Odd-Cost Edge Assignments for Tree PathsGoogleHard
- Count Pythagorean Distance Nodes in a TreeIBMMedium
Graphs0 / 57
- Enumerate Every Shortest Dictionary Transformation ChainGoogleHard
- Clone Connected Graph Nodes without Sharing Original ObjectsGoogleMedium
- Remove the Last Input Edge on the Unique CycleGoogleMedium
- Sum Importance over an Employee's Reachable SubordinatesBloombergMedium
- Combine Accounts Connected by Shared AddressesGoogleMedium
- Unlock Four Wheels with the Fewest TurnsAmazonMedium
- Seat Every Couple Together with Minimum SwapsGoogleHard
- Decide Whether an Undirected Graph Can Be Two-ColoredAmazonMedium
- Find the Cheapest Flight Route with a Stop LimitAmazonMedium
- Find Vertices from Which Every Walk TerminatesAmazonMedium
- Minimize Bus Boardings between Two StopsAmazonHard
- Reach Every Room Using Collected KeysGoogleMedium
- Find the Shortest Walk Visiting Every VertexAmazonHard
- Propagate the Quietest Known Richer PersonFlipkartMedium
- Find the Fewest Rolls through a Snakes-and-Ladders BoardAmazonMedium
- Choose One Initial Infection to Remove from an Undirected NetworkVisaHard
- Remove One Infected Vertex and Its Edges to Limit MalwareVisaHard
- Maximize Stone Removals Using Shared Rows or ColumnsPhonePeMedium
- Decide Whether Letter-Variable Equalities and Inequalities Are ConsistentAmazonMedium
- Identify a Person Trusted by Everyone Else Who Trusts NobodyAmazonEasy
- First Timestamp When All People Are ConnectedGoogleMedium
- Shortest Directed Routes With Alternating Edge ColorsGoogleMedium
- Edges Whose Removal Disconnects a NetworkInMobiHard
- Minimum Knight Steps on an Infinite BoardeBayMedium
- Smallest String Reachable Through Allowed Index SwapsGoldman SachsMedium
- Candies Reachable Through Possessed Boxes and KeysAirbnbHard
- Can Fixed-Length Jumps Reach a Zero?GoogleMedium
- Video Frequencies at One Exact Friendship DistanceAmazonMedium
- Fewest Edge Relocations to Make an Undirected Graph ConnectedAmazonMedium
- Fewest Adjacent-or-Equal-Value Jumps to the Last IndexAmazonHard
- Fewest Arrow Changes Creating a Corner-to-Corner PathAmazonHard
- Highest Product of Edge Success ProbabilitiesGoogleMedium
- Choose Starting Vertices for a DAGAndurilMedium
- Connect Planar Points at Minimum Manhattan CostGoogleMedium
- Minimize the Steepest Step on a Grid RouteGoogleMedium
- Minimize Position Mismatches Using Allowed SwapsBloombergMedium
- Identify the Hub of a Guaranteed StarAmazonEasy
- Cheapest Route Within a Travel DeadlinePhonePeHard
- Reachability Between Two Graph VerticesAmazonEasy
- Count Routes Having Minimum Travel TimeGoogleMedium
- Second Distinct Arrival Time with Synchronized SignalsGoogleHard
- Minimum Months to Finish All Courses with Durations and Unlimited ParallelismSnowflakeMedium
- Recipes That Can Be Made from Unlimited SuppliesAmazonMedium
- Largest Circular Seating with Favorite NeighborsMorgan StanleyHard
- Distance from Every Vertex to the Only CycleSalesforceHard
- Choose a Shared Reachable Node Minimizing the Worse DistanceAmazonMedium
- Measure the Longest Directed Cycle in a One-Exit GraphAndurilHard
- Count Equal-Endpoint Tree Paths Whose Interior Never Exceeds ThemGoogleHard
- Minimize a Route’s Smallest Road DistanceGoogleMedium
- Choose a Center and up to k Neighbors for Maximum Star ValueAkuna CapitalMedium
- Reach a Grid Corner with Positive HealthGoogleMedium
- Find the Methods Remaining after Removing a Suspicious GroupGoogleMedium
- Reachability Queries in a Value-Difference GraphGoogleMedium
- Shortest Paths in a Value-Difference GraphGoogleHard
- Best Recovery Score Within a Path BudgetAmazonHard
- Reach the Last Index with Prime JumpsTeradataMedium
- Maximum Value Reachable Under Directional JumpsGoogleMedium
Backtracking0 / 34
- Enumerate Balanced Parenthesis StringsAmazonMedium
- Enumerate Reusable-Value Target CombinationsGoogleMedium
- Trace a Word Through Neighboring Grid CellsAmazonMedium
- Enumerate Telephone-Keypad Letter ChoicesGoogleMedium
- Enumerate Target Combinations with Single-Use OccurrencesGoogleMedium
- Generate Every Permutation of Distinct ValuesAmazonMedium
- Generate Distinct Permutations with Repeated ValuesGoogleMedium
- List All Nonattacking Queen BoardsGoogleHard
- Enumerate Every Fixed-Size Choice from a RangeGoogleMedium
- Count Nonattacking Queen ConfigurationsMetaHard
- Enumerate All Member Choices from Distinct ValuesAmazonMedium
- Enumerate Distinct Subsets with Repeated Input ValuesMetaMedium
- Restore Dotted Addresses from an Unchanged Digit SequenceMicrosoftMedium
- Complete a Uniquely Solvable Sudoku Board in PlaceGoogleHard
- Enumerate All Contiguous Palindrome Cut ChoicesGoogleMedium
- Enumerate Fixed-Size Distinct Digit CombinationsAmazonMedium
- Recognize a Complete Additive Digit PartitionEpic SystemsMedium
- Decide Whether Four Cards Can Form Twenty-FourGoogleHard
- Count Permutations with Position DivisibilityVisaMedium
- Divide All Values into Equal-Sum GroupsAmazonMedium
- Find One Symbol in a Repeated Binary ExpansionDeshawMedium
- Enumerate Every Independent Letter-Case ChoiceGoogleMedium
- Enumerate Directed Paths between the End LabelsAmazonMedium
- Count Start-to-End Walks That Visit Every Traversable Grid Cell OnceAmazonHard
- Expand Independent Character ChoicesAndurilMedium
- Evaluate Nested Unions and Concatenations of WordsGoogleHard
- List Numbers Whose Neighboring Digits Differ by OneeBayMedium
- Longest Concatenation Without Repeated LettersAmazonMedium
- Fewest Integer Squares Tiling a RectangleGoogleHard
- Does an Injective Letter-to-Digit Sum Exist?GoogleHard
- Split into Equal-Sized Groups with Closest SumsGoogleHard
- Best Unique-Node Value on a Timed Return WalkNutanixHard
- Distribute Nine Stones Across a Three-by-Three GridAmerican ExpressMedium
- Next Palindrome with Exact Digit CountsGoogleHard
Dynamic Programming0 / 122
- Match an Entire String with Dot and StarGoogleHard
- Match a Whole String with WildcardsAmazonHard
- Count Right-and-Down Grid RoutesGoogleMedium
- Count Grid Routes Around ObstaclesAmazonMedium
- Find the Cheapest Right-and-Down Grid PathInfosysMedium
- Count Ordered One-Step and Two-Step ClimbsGoogleEasy
- Count the Fewest Character EditsInfosysMedium
- Find the Greatest Contiguous Segment SumAmazonMedium
- Recognize Recursive Split-and-Swap String TransformationsGoogleHard
- Count Complete Digit-to-Letter DecodingsGoogleMedium
- Count BST Shapes with Exact Catalan ArithmeticMetaMedium
- Recognize an Order-Preserving Merge of Two StringsAmazonMedium
- Count Position-Distinct Subsequences Matching a TargetGoogleHard
- Minimize a Triangle Path with Adjacent Downward StepsBloombergMedium
- Maximize Profit with at Most Two Chronological TradesGoogleHard
- Minimize Cuts into Palindromic String PiecesInfosysHard
- Maximize Products over Contiguous Nonempty SegmentsGoogleMedium
- Minimize Initial Health along a Right-Down Dungeon PathIntuitHard
- Maximize Nonoverlapping Trades under a Transaction CapInfosysHard
- Maximize a Nonadjacent Selection around a CircleGoogleMedium
- Measure the Largest All-One Square AreaGoogleMedium
- Enumerate Results of Every Binary ParenthesizationAmazonMedium
- Generate the One-Based Sequence of Ugly NumbersGoogleMedium
- Minimize the Number of Perfect Squares Summing to an IntegerMetaMedium
- Measure a Strictly Increasing SubsequenceMicrosoftMedium
- Maximize Coins from Bursting All BalloonsGoogleHard
- Find the Longest Strictly Increasing Cardinal Matrix PathGoogleHard
- Maximize Nonadjacent Value Selection on a Binary TreeAmazonMedium
- Maximize the Product of a Positive Integer SplitTCSMedium
- Compute the Fibonacci Value at an IndexMetaEasy
- Measure the Longest Palindromic SubsequenceMicrosoftMedium
- Maximize the Score from Removing Equal-Color RunsGoogleHard
- Minimize Single-Character Deletions to Equalize Two WordsBloombergMedium
- Buy Exact Item Quantities Using Reusable BundlesGoogleMedium
- Minimize Overwriting Turns of a Single-Character PrinterMastercardHard
- Count All Maximum-Length Strictly Increasing SubsequencesGoogleMedium
- Compute Knight Survival Probability after K Random MovesAppleMedium
- Choose Three Disjoint Equal-Length Windows with Lexicographic TiesAmazonHard
- Trade Repeatedly with a Fee per Completed TransactionInfosysMedium
- Measure a Shared Contiguous Array BlockGoogleMedium
- Choose Values without Earning from Adjacent ValuesWalmart LabsMedium
- Collect Cherries on an Outward and Return TripInMobiHard
- Reach the Staircase Top at Minimum CostGoogleEasy
- Count Tilings with Dominoes and L-Shaped TrominoesGoldman SachsMedium
- Split All Values into Two Equal-Average GroupsAmazonHard
- Compute the Chance of Finishing below a Score LimitMicrosoftMedium
- Maximize the Sum of a Nonempty Circular Array SegmentMicrosoftMedium
- Count Fixed-Length Playlists That Use Every Song with a Replay GapServiceNowHard
- Minimize a Top-to-Bottom Path with Adjacent-Column StepsGoogleMedium
- Count Digit Strings Produced by Knight Moves on a Phone PadWhatnotMedium
- Count Distinct Nonempty Subsequences of a Lowercase StringGoogleHard
- Count Starts That Reach the End under Alternating Ordered JumpsGoogleHard
- Cover Listed Travel Days with Minimum Pass CostInfosysMedium
- Minimize the Cost of Merging Exactly K Adjacent Piles at a TimeAmazonHard
- Maximize the Total of Two Disjoint Fixed-Length SegmentsSprinklrMedium
- Best Total After Bounded Block ReplacementInfosysMedium
- Longest Chain of Single-Letter InsertionsGoogleMedium
- Smallest Residue From Freely Chosen Stone SmashesAppleMedium
- Build a Shortest String Containing Two SubsequencesGoogleHard
- Fewest People Covering Every Required SkillAirbnbHard
- Compute a Three-Term RecurrenceGoogleEasy
- Optimal First-Player Stones With a Growing Take LimitGoogleMedium
- Length of a Longest Shared SubsequenceAppleMedium
- Count Ordered Dice Outcomes With a Given TotalGoogleMedium
- Best Nonempty Subarray After At Most One ErasureGoogleMedium
- Maximum Subarray Sum in Repeated CopiesAmazonMedium
- Largest Subset Sum Divisible by ThreeGarenaMedium
- Count Every All-One Square in a Binary MatrixDevRevMedium
- Best Upward Board Score and Number of Optimal RoutesGoogleHard
- Fewest Insertions Needed for a PalindromeAmazonHard
- Least Two-Finger Travel on the Six-Column KeyboardGoogleHard
- Minimum Sum of Daily Job-Difficulty MaximaMicrosoftHard
- Most Indices Visited by Bounded Downhill JumpsGoogleHard
- Largest Share from the Circular Pizza Selection GameInfosysHard
- Winner of the Optimal One-to-Three Stone GameGoogleHard
- Count Distinct Preferred-Hat AssignmentsRobloxHard
- Maximum Cherries Collected by Two Descending RobotsAmazonHard
- Shortest Combined Length of Two Disjoint Target-Sum WindowsGoogleMedium
- Minimum House-to-Mailbox Distance with k MailboxesGoogleHard
- Minimum Semesters with Prerequisites and a Course LimitAmazonHard
- Winner When Each Move Removes a Positive SquareBloombergHard
- Minimum Total Cost of All Required Stick CutsAmazonHard
- Finish the Orange Supply in the Fewest DaysAmazonHard
- Maximize the Score from Repeated Row SplitsInfosysHard
- Choose a Maximum-Score Conflict-Free TeamThoughtSpotMedium
- Build a Target from Increasing Dictionary ColumnsUberHard
- Stack Rotatable Cuboids for Maximum HeightAmazonHard
- Maximize the Score of Bounded Forward JumpsMicrosoftMedium
- Choose Valuable Events with an Attendance LimitGrowwHard
- Pair Values with Increasing GCD MultipliersGrowwHard
- Cross a Three-Lane Road with Few Side JumpsInfosysMedium
- Check Whether Bounded Jumps Reach the Final IndexBloombergMedium
- Compute the Optimal Prefix-Merging Game DifferenceInfosysHard
- Best Alternating Sum of an Ordered SelectionGoogleMedium
- Choose Exam Questions with Forced SkipsGoogleMedium
- Test Whether a Right-and-Down Grid Path Forms Balanced ParenthesesAmazonHard
- Maximize the Difference between Two Present Letter CountsAmazonHard
- Maximize Revenue from Rectangular Wood CutsThoughtSpotHard
- Track Daily Secret Sharing before Each Person ForgetsBloombergMedium
- Keep the Longest Subsequence with Bounded Alphabet GapsInfosysMedium
- Find a Strictly Increasing Subsequence with Limited Numeric StepsGoogleHard
- Count Binary Strings Built from Fixed Zero and One BlocksVisaMedium
- Select the Most Disjoint Palindromic Substrings of Sufficient LengthGoogleHard
- Count Five-Position Palindromes in a Digit StringVisaHard
- Paint Every Wall at Minimum Cost with Two PaintersAmazonHard
- Maximize Forward Jumps to the Last Array IndexAmazonMedium
- Count Stepping Numbers Between Two String BoundsAmazonHard
- Total Power Across All SubsequencesTeradataHard
- Fewest Substrings with Equal Character FrequenciesGrammarlyMedium
- Minimum-Score Array PermutationGoogleHard
- Longest Subsequence with at Most k Value ChangesBNY MellonHard
- Score a Grid After Coloring Column PrefixesGoogleHard
- Count Disjoint Subsequence Pairs with Equal GCDMetaHard
- Choose Up to Four Non-overlapping IntervalsAmazonHard
- Count Prefix and Suffix Removals by Product RemainderGoogleMedium
- Maximum Profit from Normal and Short TransactionsGoogleMedium
- Recover Coin Denominations from Combination CountsGoogleMedium
- Maximum Sum of an Increasing-Decreasing-Increasing SubarrayInMobiHard
- Count Arrays with Zigzag ComparisonsGoogleHard
- Count Zigzag Arrays with Large LengthGoogleHard
- Maximum Grid Path Score Within a BudgetGoogleMedium
- Total Digit Waviness Across a Large RangeBloombergHard
Greedy0 / 73
- Reach the Last Index in the Fewest JumpsAmazonMedium
- Maximize One Chronological Stock TransactionGoogleEasy
- Maximize Repeated One-Share Stock Trading ProfitGoogleMedium
- Find the Unique Start for a Circular Fuel CircuitAmazonMedium
- Minimize Candy Counts under Adjacent Rating ComparisonsAmazonHard
- Keep One of Each Letter in the Smallest SubsequenceAmazonMedium
- Detect a Strictly Increasing Three-Index PatternAmazonMedium
- Grow Capital by Selecting Affordable ProjectsGoogleHard
- Balance Dresses Across Adjacent Washing MachinesAmazonHard
- Find the Next Larger Integer with the Same DigitsBloombergMedium
- Maximize the Sum of Pair MinimaMicrosoftEasy
- Check Whether More Flowers Fit without Adjacent PlantsLinkedInEasy
- Minimize CPU Intervals with Equal-Label CooldownsAmazonMedium
- Complete as Many Deadline-Bounded Courses as PossibleSuperMoneyHard
- Maximize an Integer with at Most One Digit SwapNielsenMedium
- Validate Parentheses with Optional Wildcard CharactersGoogleMedium
- Split a String into the Most Letter-Disjoint PiecesGoogleMedium
- Assign Each Worker Its Best Feasible Reusable JobGoogleMedium
- Partition Cards into Consecutive Equal-Sized GroupsGoogleMedium
- Give Correct Change to Customers in OrderInfosysEasy
- Maximize Binary Row Values with Row and Column TogglesAmazonMedium
- Reorder One Array to Win as Many Position Comparisons as PossibleSquarepointMedium
- Minimize Two-Person Boats under a Weight LimitGoogleMedium
- Construct a Permutation Matching Consecutive Increase and Decrease SignsGoogleEasy
- Choose Three Lengths with the Largest Nondegenerate Triangle PerimeterGoogleEasy
- Maximize Array Sum after Exactly K Sign ChangesInfosysEasy
- Minimize Travel Cost while Sending Half the People to Each CityInfosysMedium
- Fewest Subsequences of a Source String That Concatenate to a Target StringPinterestHard
- Maximum Number of Balanced L/R PiecesInfosysEasy
- Choose and Order Dishes for Maximum Weighted SatisfactionTeradataHard
- Schedule Dry Days to Prevent Any Lake FloodMongoDBMedium
- Fewest Interval Increments to Build a Target SkylineAmazonHard
- Minimum Adjacent Row Swaps for Zeros Above the DiagonalAmazonMedium
- Pack Boxes Through a One-Sided WarehousePinterestMedium
- Arrange Values to Maximize Range RequestsGoogleMedium
- Reach the Furthest Building with Limited Climbing SuppliesAmazonMedium
- Maximize Revenue from Falling Color InventoriesIBMMedium
- Schedule Tasks with the Least Starting EnergyGoogleHard
- Load a Truck with the Most UnitsInfosysEasy
- Equalize Two Dice-Valued Array SumsInfosysMedium
- Increase Values Just Enough for Strict OrderInfosysEasy
- Build the Highest Valid Value by Decreasing and RearrangingGoogleMedium
- Fewest Arbitrary Bracket SwapsInfosysMedium
- Minimum Cost to Move a Robot HomeJuspayMedium
- Can a Growing Planet Absorb Every Asteroid?MicrosoftMedium
- Buy All Items Under a Two-Paid One-Free OfferAmazonEasy
- Split a Sum into as Many Distinct Positive Evens as PossibleGoogleMedium
- Finish the Greatest Number of Partially Filled BagsInfosysMedium
- Use the Fewest Value-Range-Bounded SubsequencesAmazonMedium
- Spend Unit Changes to Minimize Squared Pair DifferencesGoogleMedium
- Split Values into the Fewest Pieces for Nondecreasing OrderSalesforceHard
- Build the Greatest Non-Leading-Zero Palindrome from Available DigitsAmazonMedium
- Partition a String into the Fewest Duplicate-Free PiecesAmazonMedium
- Move Units Left to Minimize the Largest Array ValueVisaMedium
- Minimize the Longest Jump on a Round Trip through Ordered StonesGoogleMedium
- Compare the Highest and Lowest Scores from k Contiguous BagsSalesforceHard
- Maximize Eight-Dollar Shares without Giving Anyone FourMongoDBEasy
- Maximize Strict Wins by Permuting the Same MultisetMicrosoftMedium
- Choose Exactly k Ones, Zeros, and Negative Ones for the Greatest SumGoogleEasy
- Insert the Fewest Letters to Form Repeated abc BlocksIBMMedium
- Find the Minimum Cost to Equalize a Binary StringAmazonMedium
- Minimize the Finish Time of Tasks on Four-Core ProcessorsJPMorgan ChaseMedium
- Minimum Adjacent Swaps to Place White Balls Before Black BallsAmazonMedium
- Fewest Keypresses After Remapping Distinct LettersGoogleEasy
- Fewest Keypresses After Remapping Letters That May RepeatAmazonMedium
- Assign Distinct Tower Heights Under Per-Tower LimitsGuidewireMedium
- Smallest Index Sequence Matching a Target with at Most One ChangeGoogleMedium
- Maximum Grid Selection Sum Under Row LimitsAmazonMedium
- Least Permutation Strictly Above a TargetAmazonMedium
- Largest Integer with a Maximum Digit-Square ScoreGoogleMedium
- Maximum Alternating Squared ScoreGoogleMedium
- Least Palindromic Permutation Above a TargetGoogleHard
- Least Signed Permutation with a Target SumAmazonMedium
Heaps & Priority Queues0 / 16
- Select a Kth-Largest Occurrence without Full SortingAmazonMedium
- Select the Smallest Cross-Array Pair SumsMicrosoftMedium
- Find the Narrowest Interval Meeting Every Sorted ListAmazonHard
- Hire an Exactly Sized Group with Proportional PayAppleHard
- Minimize Refueling Stops on a One-Direction JourneyAmazonHard
- Return the K Nearest Input Points to the OriginAmazonMedium
- Final Weight Under Heaviest-Pair SmashingAppleEasy
- Average Each Student's Five Highest ScoresGoldman SachsEasy
- Maximum Team Performance with a Size LimitMicrosoftHard
- Shrink the Reachable Value RangeBloombergHard
- Match Buy and Sell Batches and Count the BacklogCitadelMedium
- Simulate a Nonpreemptive CPU with Deterministic TiesAmazonMedium
- Reduce Piles with Repeated Half RemovalsSalesforceMedium
- Halve the Total with the Fewest Exact ReductionsNutanixMedium
- Choose k Paired Indices to Maximize Sum Times MinimumDevRevMedium
- Maximum Total Subarray Range from Distinct ChoicesGoogleHard
Intervals0 / 25
- Construct Canonical Skyline Height-Change PointsMicrosoftHard
- Cover Sorted Unique Integers with Minimal Exact RangesGoogleEasy
- Track Coverage of Half-Open Real IntervalsGoogleHard
- Book Events without Overlapping TimeAmazonMedium
- Return Finite Gaps Shared by Every ScheduleGoogleHard
- Intersect Two Sorted Lists of Disjoint Closed IntervalsMetaMedium
- Check Capacity Along Eastbound TripsAmazonMedium
- Seat Totals Across Inclusive Flight BookingsMicrosoftMedium
- Choose Non-Overlapping Weighted Jobs to Maximize Total ProfitGoogleMedium
- Count Intervals Not Contained in AnotherAmazonMedium
- Open the Minimum Number of Sprinklers to Cover a GardenQuinceMedium
- Largest Number of One-Day Event AttendancesMicrosoftMedium
- Most Disjoint Character-Closed Substrings with Minimum Total LengthGoogleHard
- Answer Queries with the Shortest Covering IntervalGoogleHard
- Choose the Earliest Year of Peak PopulationGoogleEasy
- Find the Integer Point Covered by the Most Street LampsCapital OneMedium
- Best Value from Up to Two Separate EventsGrammarlyMedium
- Count Street Positions Meeting Their Light RequirementCapital OneMedium
- Count Inclusive Bloom Intervals at Each Visitor TimeRobloxHard
- Cover the Most White Integer Tiles with One CarpetAmazonMedium
- Assign meetings to rooms with delaysGoogleMedium
- Count Workdays without Any MeetingBloombergMedium
- Max total of k consecutive bags over disjoint valued segments, modulo 1e9+7AmazonMedium
- Finish One Land Ride and One Water RideAmazonEasy
- Finish a Land and Water Ride from Large ListsGoogleMedium
Grids & Matrices0 / 46
- Measure the Largest All-One Grid RectangleAmazonHard
- Read a Matrix Along Its Inward SpiralGoogleMedium
- Fill a Square with Consecutive Spiral ValuesAmazonMedium
- Clear Rows and Columns Triggered by Original ZerosAmazonMedium
- Capture Letter Regions Disconnected from the Board EdgeAmazonMedium
- Fill Rooms with Their Nearest Gate DistancesAmazonMedium
- Advance a Binary Life Board Simultaneously In PlaceAmazonMedium
- Compute Every Binary Cell Distance to a ZeroAmazonMedium
- Reshape a Matrix while Preserving Row OrderGoogleEasy
- Count Island Shapes up to Translation OnlyAndurilMedium
- Stabilize a Board by Simultaneous MatchesRobloxMedium
- Recolor the Connected Component of a PixelAmazonEasy
- Quarantine the Region Threatening the Most CellsFlipkartHard
- Check Constant Values along Down-Right DiagonalsTCSEasy
- Grow the Largest Island by Changing at Most One CellTikTokHard
- Reverse Each Binary Row and Invert Its BitsGoogleEasy
- Maximize Binary Image Overlap by TranslationGoogleMedium
- Find the Fewest Grid Moves Needed to Collect Every KeyGoogleHard
- Swap Row and Column Indices of a Rectangular MatrixAmazonEasy
- Simulate Obstacle-Aware Robot Moves and Track the Farthest PointShopifyMedium
- List Grid Cells Encountered by an Expanding Clockwise SpiralBloombergMedium
- Fewest Clear Cells From Corner to CornerGoogleMedium
- Shortest Selection Walk on the Alphabet BoardAtlassianMedium
- Count Land Components Enclosed Away From the BoundaryGoogleMedium
- Rotate a Grid in Row-Major OrderGoogleEasy
- Shortest Four-Direction Route With an Obstacle BudgetGoogleHard
- Clipped Square-Neighborhood Sums for Every Matrix CellAmazonMedium
- Values That Are Row Minima and Column MaximaGoogleEasy
- Check a Path Through Mutually Connected Street TilesGoogleMedium
- Find a Same-Letter Loop in a GridAmazonMedium
- Sum the Two Diagonals Without Double CountingGoogleEasy
- Find the Largest Customer Account TotalGoogleEasy
- Rotate a Stone Box and Settle Its ContentsGoogleMedium
- Check Whether Quarter-Turns Match a Target MatrixBloombergEasy
- Rotate Every Rectangular RingGoogleMedium
- Latest Flooding Day with a Land CrossingGoogleHard
- Wait as Long as Possible before Escaping a Spreading FireUberHard
- Solve BST and Grid Query ProblemsUberMedium
- Find the Earliest Row with the Most OnesAmazonEasy
- Find the First Paint Step Completing a Row or ColumnAmazonMedium
- Sum a Matrix After Row and Column AssignmentsSalesforceMedium
- Find the Maximum Safeness of a Grid PathGoogleMedium
- Count Top-Left-Anchored Submatrices Within a Sum LimitNatwestMedium
- Find the Earliest Matrix Match for a Digit-and-Letter PatternRobloxMedium
- Longest Diagonal Segment with at Most One Clockwise TurnAmazonHard
- Minimum Moves to Collect Classroom LitterAmazonMedium
Bit Manipulation0 / 19
- Recover the Value Left after Pair CancellationGoogleEasy
- Recover a Signed Value among Threefold RepetitionsGoogleMedium
- Reverse All Bits of an Even Signed IntegerBloombergEasy
- Count Set Bits in a Positive Signed IntegerGoogleEasy
- Recover Two Singly Occurring Signed ValuesAmazonMedium
- Check Adjacent Bits in a Positive IntegerGoogleEasy
- Use the Fewest Fixed-Length Bit Flips to Make Every Bit OneGoogleHard
- XOR the Arithmetic-Step ArrayAmazonEasy
- Count Substrings with Almost-Even Letter CountsUberMedium
- Fewest Add-or-Subtract Power-of-Two Steps to Reduce n to ZeroSalesforceMedium
- Maximize the Bitwise OR Within a Doubling BudgetVisaMedium
- Maximize the Sum of Squares After Bitwise Pair OperationsGoogleHard
- Maximize a Product Under a Shared Bounded XOR ChoiceZomatoMedium
- Count Distinct XOR Values from Index TriplesGoogleMedium
- Distinct XOR Results from Three Array ChoicesAmazonMedium
- Largest Fixed AND Value for Sorting a PermutationAmazonMedium
- Longest Subsequence with a Nonzero XORGoogleMedium
- Maximize the Bitwise AND of K Elements After Spending an Increment BudgetAmazonHard
- Maximum Binary XOR After Rearranging One StringMicrosoftMedium
Math0 / 105
- Check a Decimal Integer for SymmetryGoogleEasy
- Multiply Two Decimal Digit StringsAmazonMedium
- Add Two Binary Digit StringsGoogleEasy
- Reverse Decimal Digits Within Signed 32-Bit LimitsGoogleMedium
- Encode an Integer with Standard Roman SymbolsAmazonMedium
- Evaluate a Guaranteed-Valid Roman NumeralGoogleEasy
- Compute a Quotient Using Signed 32-Bit OperationsGoogleMedium
- Evaluate a Floating Base to an Integer PowerGoogleMedium
- Select a Permutation by Its Lexicographic RankGoogleHard
- Generate the First Rows of Pascal CoefficientsGoogleEasy
- Compute One Zero-Indexed Pascal RowAmazonEasy
- Format Exact Fractions with Parenthesized Repeating DigitsGoldman SachsMedium
- Count Collinear Points with Exact Integer DirectionsGoogleHard
- Convert Positive Column Numbers to Uppercase Letter TitlesBloombergEasy
- Decode Uppercase Spreadsheet Column TitlesGoogleEasy
- Count Decimal Zeros at the End of a FactorialGoogleMedium
- Recognize Digit-Square Sequences That Reach OneGoogleEasy
- Count Primes Strictly before an Integer BoundGoogleMedium
- Compute Two-Rectangle Coverage from Eight CoordinatesGoogleMedium
- Count Decimal One Digits up to a BoundGoogleHard
- Reduce a Decimal Integer to One DigitGoogleEasy
- Recognize Positive Numbers with Only Three Allowed Prime FactorsGoogleEasy
- Spell a Nonnegative Signed Integer in English WordsAmazonHard
- Decide the Winner of One-to-Three Stone NimMetaEasy
- Count Bulbs Left On after Divisor-Indexed TogglesLinkedInMedium
- Recognize Powers of Three without IterationGoogleEasy
- Write an Integer Using Base Seven DigitsGoogleEasy
- Check the Sum of Proper Positive DivisorsAmazonEasy
- Find the Nearest Different Decimal PalindromeAmazonHard
- Choose Three Values with the Largest ProductGoogleEasy
- Decide Whether an Integer Is a Sum of Two SquaresAmazonMedium
- Reach a Signed Destination with Increasing Step SizesGoogleMedium
- Reverse Additive Coordinate MovesVirtu FinancialHard
- Count Numbers Changed by Valid Digit RotationGoogleMedium
- Test for a Positive-Area Rectangle IntersectionGoogleEasy
- Decide the Winner of Optimal End-Pile Stone SelectionGoogleMedium
- Locate the Nth Positive Multiple of Either of Two DivisorsGoogleHard
- Construct a Permutation without an Ordered Arithmetic TripleGoogleMedium
- Find the Smallest Rectangle Area with Arbitrarily Oriented SidesGoogleMedium
- Add an Integer to a Number Represented as Decimal DigitsGoogleEasy
- Find the Shortest All-One Decimal Integer Divisible by KAmazonMedium
- Determine the Winner of Repeated Proper-Divisor SubtractionAmazonEasy
- Longest Repeated Block Shared by Two StringsGoogleEasy
- Shorter Distance Around a Ring of Bus StopsAmazonEasy
- Weekday of a Valid Gregorian DateGoogleEasy
- Cheapest Way to Gather Chips at One PositionInfosysEasy
- Fastest Ordered Visit of Integer PointsAmazonEasy
- Digit Product Minus Digit SumGoogleEasy
- Sorted Integers With Consecutively Increasing DigitsGoogleMedium
- Count Integers With an Even Decimal LengthGoogleEasy
- Count the Forced Halve-or-Decrement StepsGoogleEasy
- Find the Smaller Angle Between Clock HandsAmazonMedium
- Days Between Two Calendar DatesOptiverMedium
- Kth Positive Factor in Ascending OrderAmazonMedium
- Maximum Drinks from Full Bottles and Empty-Bottle ExchangesGoogleEasy
- Count Odd Integers in an Inclusive RangeAmazonEasy
- Rotate a View to See the Most PointsAndurilHard
- Count Collections of Nonoverlapping SegmentsGoogleMedium
- Minimize the Floor Footprint of Supported BoxesAdobeHard
- Find the Period of a Perfect InterleavingTCSMedium
- Return the Sign of an Array's ProductGoogleEasy
- Find the Survivor of Clockwise EliminationAmazonMedium
- Count Points in Inclusive Circular QueriesAndurilMedium
- Maximize the Skyline Under Sparse Height CapsMetaHard
- Count Position-Constrained Digit StringsMetaMedium
- Decide the Winner of a Digit-Balance GameAmazonMedium
- Test for Exactly Three Positive DivisorsBloombergEasy
- GCD of the Two Extreme Array ValuesAmazonEasy
- Winner Under a Divisible-by-Three Losing RuleAmazonMedium
- Place Parentheses for the Least Expression ValueCapital OneMedium
- Sum Two Bounded Signed IntegersGoogleEasy
- Compute Progressive Income Tax in Cents from Bracket LimitsSnowflakeMedium
- Count Positive Numbers with No Repeated Decimal DigitGoogleHard
- Check Palindromic Digits in Every Required BaseGoogleMedium
- Return the Least Positive Number Divisible by Two and nGoogleEasy
- Choose a Shared Array Value with Minimum Weighted Unit CostAmazonHard
- Convert Celsius to Kelvin and Fahrenheit in the Required OrderAmazonEasy
- Find the Integer Shared by Two Equal Inclusive Range SumsGoogleEasy
- Count Digit Occurrences That Divide the Original NumberAmazonEasy
- Add the Integers Divisible by Three, Five, or SevenAmazonEasy
- Sum Robot Distances After Motion and CollisionsOYOMedium
- Sum Squared Values at Special Array PositionsBloombergEasy
- Maximize Final Distance After Fixed and Flexible MovesMetaEasy
- Difference Between Nondivisible and Divisible SumsGoogleEasy
- Solve Three Array Coding ProblemsVisaMedium
- Largest Selection That Forms a Symmetric Power PatternMetaMedium
- Kth Distinct Amount Using One DenominationMicrosoftHard
- Find the Smallest Value After One Digit-Sum ReplacementGoogleEasy
- Answer Sorted Pair-GCD Position QueriesGoogleHard
- Find the Next Number with a Divisible Digit ProductGoogleEasy
- Find the Smallest Zero-Free Number with a Divisible Digit ProductGoogleHard
- Count Splits with an Even Sum DifferenceGoogleEasy
- Maximum Minimum Manhattan Distance on a Square BoundaryGoogleHard
- Count Distinct Three-Digit Even NumbersGoogleEasy
- Unit Ratio Queries Across Independent Unit Families with Modular AnswersAppleMedium
- Maximum Product of Two Decimal DigitsGoogleEasy
- Divisibility by Combined Digit ValuesGoogleEasy
- Solve load balancing and perfect pairsMicrosoftMedium
- Greatest Common Divisor of Odd and Even SumsGoogleEasy
- Total Digit Waviness Across a RangeAmazonMedium
- Remove Zero Digits and Multiply by Their SumMicrosoftEasy
- GCD Sum of Prescribed Derived-Value PairsAmazonMedium
- Total Commas in a Bounded Integer RangeGoogleEasy
- Total Commas Across a Large Integer RangeGoogleMedium
- Feasibility of a Uniform-Parity ConstructionGoogleEasy
Data Structure Design0 / 41
- Maintain Stack Values and Historical Prefix MinimaGoogleMedium
- Maintain LIFO Behavior Using Only FIFO Queue OperationsGoogleEasy
- Implement FIFO Operations with Two StacksGoogleEasy
- Preprocess Word Positions for Repeated Distance QueriesPalantirMedium
- Preprocess Immutable Inclusive Array Range SumsGoogleEasy
- Answer Immutable Rectangle Sums in Constant Query TimeGoogleMedium
- Maintain Inclusive Array Sums across Point AssignmentsAmazonMedium
- Iterate NestedInteger Contents in Their Original Flattened OrderAmazonMedium
- Maintain a Windowed Moving Average across Stream CallsSpotifyEasy
- Track Tic-Tac-Toe Winners across Valid Alternating MovesWiseMedium
- Implement Posting and Follow-Based Recent Tweet FeedsGoogleMedium
- Maintain Spreadsheet Cells with Persistent Sum DependenciesAirbnbHard
- Search a Dictionary after Exactly One Character ReplacementBloombergMedium
- Seat Arrivals at the Farthest Available PositionAppleMedium
- Consume a Run-Length Encoded Sequence through a Stateful IteratorGoogleMedium
- Maintain an Inclusive Three-Second Request WindowGoogleEasy
- Store Timestamped Values and Retrieve the Latest Eligible VersionCitadelMedium
- Array Values at Saved Snapshot VersionsAppleMedium
- Create and Query Hierarchical Path ValuesGoogleMedium
- Implement a Duplicate-Aware Layered Skip ListOptiverHard
- Scores and Top-K Totals on a LeaderboardGoogleMedium
- Count Named Records in Minute, Hour or Day BucketsIntercomMedium
- Average Travel Times for Directed Station PairsBloombergMedium
- First Value Appearing Exactly Once in an Append-Only QueueAmazonMedium
- Single-Tab Browser Navigation HistoryChimeMedium
- Maintain a Royal Family’s Succession OrderSnowflakeMedium
- Track Capacity in Three Parking CategoriesMicrosoftEasy
- Manage Authentication Tokens with a Fixed Time to LiveIBMMedium
- Maintain a Priced Movie Loan CatalogOktaHard
- A Tree with User-Owned LocksJuspayMedium
- Count Axis-Aligned Squares in a Point StreamAmazonMedium
- Correct and Query Timestamped PricesGoogleMedium
- Validate Stateful Account TransactionsCapital OneMedium
- Answer Repeated Range-Frequency QueriesAmazonMedium
- Count Dictionary Originals Sharing an EncryptionDuolingoHard
- Maintain Editable Text around a Bounded CursorSquarepointHard
- Implement a Contiguous Memory ManagerOpenAIHard
- Manage Pending Tasks with Global IDs and Due-Date OrderingBloombergMedium
- Manage Tasks with Priority and Task-ID Execution RulesAmazonMedium
- Design a Spreadsheet with Cell Updates and Sum QueriesCitadelMedium
- Ride Sharing with Ordered Matching and CancellationRipplingMedium