PhantomCodeAIPhantomCodeAI
FeaturesMock InterviewDashboardJobsPricing
FeaturesMock InterviewDashboardJobsPricing
PhantomCodeAIPhantomCodeAI
FeaturesMock InterviewDashboardJobsPricing
FeaturesMock InterviewDashboardJobsPricing
HomeLeetCode ProblemsString

String Problems

699 String LeetCode problems · Solve with AI-powered hints & step-by-step explanations.

3Longest Substring Without Repeating CharactersMedium5Longest Palindromic SubstringMedium6Zigzag ConversionMedium8String to Integer (atoi)Medium10Regular Expression MatchingHard12Integer to RomanMedium13Roman to IntegerEasy14Longest Common PrefixEasy17Letter Combinations of a Phone NumberMedium20Valid ParenthesesEasy22Generate ParenthesesMedium28Find the Index of the First Occurrence in a StringEasy30Substring with Concatenation of All WordsHard32Longest Valid ParenthesesHard38Count and SayMedium43Multiply StringsMedium44Wildcard MatchingHard49Group AnagramsMedium58Length of Last WordEasy65Valid NumberHard67Add BinaryEasy68Text JustificationHard71Simplify PathMedium72Edit DistanceMedium76Minimum Window SubstringHard79Word SearchMedium87Scramble StringHard91Decode WaysMedium93Restore IP AddressesMedium97Interleaving StringMedium115Distinct SubsequencesHard125Valid PalindromeEasy126Word Ladder IIHard127Word LadderHard131Palindrome PartitioningMedium132Palindrome Partitioning IIHard139Word BreakMedium140Word Break IIHard151Reverse Words in a StringMedium165Compare Version NumbersMedium166Fraction to Recurring DecimalMedium168Excel Sheet Column TitleEasy171Excel Sheet Column NumberEasy179Largest NumberMedium187Repeated DNA SequencesMedium205Isomorphic StringsEasy208Implement Trie (Prefix Tree)Medium211Design Add and Search Words Data StructureMedium212Word Search IIHard214Shortest PalindromeHard224Basic CalculatorHard227Basic Calculator IIMedium241Different Ways to Add ParenthesesMedium242Valid AnagramEasy257Binary Tree PathsEasy273Integer to English WordsHard282Expression Add OperatorsHard290Word PatternEasy297Serialize and Deserialize Binary TreeHard299Bulls and CowsMedium301Remove Invalid ParenthesesHard306Additive NumberMedium316Remove Duplicate LettersMedium318Maximum Product of Word LengthsMedium331Verify Preorder Serialization of a Binary TreeMedium336Palindrome PairsHard344Reverse StringEasy345Reverse Vowels of a StringEasy383Ransom NoteEasy385Mini ParserMedium387First Unique Character in a StringEasy388Longest Absolute File PathMedium389Find the DifferenceEasy392Is SubsequenceEasy394Decode StringMedium395Longest Substring with At Least K Repeating CharactersMedium399Evaluate DivisionMedium402Remove K DigitsMedium405Convert a Number to HexadecimalEasy409Longest PalindromeEasy412Fizz BuzzEasy415Add StringsEasy420Strong Password CheckerHard423Reconstruct Original Digits from EnglishMedium424Longest Repeating Character ReplacementMedium433Minimum Genetic MutationMedium434Number of Segments in a StringEasy438Find All Anagrams in a StringMedium443String CompressionMedium449Serialize and Deserialize BSTMedium451Sort Characters By FrequencyMedium459Repeated Substring PatternEasy466Count The RepetitionsHard467Unique Substrings in Wraparound StringMedium468Validate IP AddressMedium472Concatenated WordsHard474Ones and ZeroesMedium481Magical StringMedium482License Key FormattingEasy488Zuma GameHard500Keyboard RowEasy504Base 7Easy514Freedom TrailHard516Longest Palindromic SubsequenceMedium520Detect CapitalEasy521Longest Uncommon Subsequence IEasy522Longest Uncommon Subsequence IIMedium524Longest Word in Dictionary through DeletingMedium535Encode and Decode TinyURLMedium537Complex Number MultiplicationMedium539Minimum Time DifferenceMedium541Reverse String IIEasy551Student Attendance Record IEasy556Next Greater Element IIIMedium557Reverse Words in a String IIIEasy564Find the Closest PalindromeHard567Permutation in StringMedium583Delete Operation for Two StringsMedium591Tag ValidatorHard592Fraction Addition and SubtractionMedium599Minimum Index Sum of Two ListsEasy606Construct String from Binary TreeMedium609Find Duplicate File in SystemMedium639Decode Ways IIHard640Solve the EquationMedium647Palindromic SubstringsMedium648Replace WordsMedium649Dota2 SenateMedium657Robot Return to OriginEasy664Strange PrinterHard676Implement Magic DictionaryMedium677Map Sum PairsMedium678Valid Parenthesis StringMedium680Valid Palindrome IIEasy686Repeated String MatchMedium691Stickers to Spell WordHard692Top K Frequent WordsMedium696Count Binary SubstringsEasy709To Lower CaseEasy712Minimum ASCII Delete Sum for Two StringsMedium720Longest Word in DictionaryMedium721Accounts MergeMedium722Remove CommentsMedium726Number of AtomsHard730Count Different Palindromic SubsequencesHard736Parse Lisp ExpressionHard745Prefix and Suffix SearchHard748Shortest Completing WordEasy752Open the LockMedium761Special Binary StringHard763Partition LabelsMedium767Reorganize StringMedium770Basic Calculator IVHard771Jewels and StonesEasy777Swap Adjacent in LR StringMedium784Letter Case PermutationMedium791Custom Sort StringMedium792Number of Matching SubsequencesMedium796Rotate StringEasy804Unique Morse Code WordsEasy806Number of Lines To Write StringEasy809Expressive WordsMedium811Subdomain Visit CountMedium816Ambiguous CoordinatesMedium819Most Common WordEasy820Short Encoding of WordsMedium821Shortest Distance to a CharacterEasy824Goat LatinEasy828Count Unique Characters of All Substrings of a Given StringHard830Positions of Large GroupsEasy831Masking Personal InformationMedium833Find And Replace in StringMedium838Push DominoesMedium839Similar String GroupsHard842Split Array into Fibonacci SequenceMedium843Guess the WordHard844Backspace String CompareEasy848Shifting LettersMedium854K-Similar StringsHard856Score of ParenthesesMedium859Buddy StringsEasy880Decoded String at IndexMedium884Uncommon Words from Two SentencesEasy890Find and Replace PatternMedium893Groups of Special-Equivalent StringsMedium899Orderly QueueHard902Numbers At Most N Given Digit SetHard903Valid Permutations for DI SequenceHard906Super PalindromesHard916Word SubsetsMedium917Reverse Only LettersEasy921Minimum Add to Make Parentheses ValidMedium925Long Pressed NameEasy926Flip String to Monotone IncreasingMedium929Unique Email AddressesEasy936Stamping The SequenceHard937Reorder Data in Log FilesMedium940Distinct Subsequences IIHard942DI String MatchEasy943Find the Shortest SuperstringHard944Delete Columns to Make SortedEasy949Largest Time for Given DigitsMedium953Verifying an Alien DictionaryEasy955Delete Columns to Make Sorted IIMedium960Delete Columns to Make Sorted IIIHard966Vowel SpellcheckerMedium972Equal Rational NumbersHard981Time Based Key-Value StoreMedium984String Without AAA or BBBMedium988Smallest String Starting From LeafMedium990Satisfiability of Equality EquationsMedium1002Find Common CharactersEasy1003Check If Word Is Valid After SubstitutionsMedium1016Binary String With Substrings Representing 1 To NMedium1021Remove Outermost ParenthesesEasy1023Camelcase MatchingMedium1028Recover a Tree From Preorder TraversalHard1032Stream of CharactersHard1041Robot Bounded In CircleMedium1044Longest Duplicate SubstringHard1047Remove All Adjacent Duplicates In StringEasy1048Longest String ChainMedium1061Lexicographically Smallest Equivalent StringMedium1071Greatest Common Divisor of StringsEasy1078Occurrences After BigramEasy1079Letter Tile PossibilitiesMedium1081Smallest Subsequence of Distinct CharactersMedium1092Shortest Common Supersequence Hard1096Brace Expansion IIHard1106Parsing A Boolean ExpressionHard1108Defanging an IP AddressEasy1111Maximum Nesting Depth of Two Valid Parentheses StringsMedium1138Alphabet Board PathMedium1143Longest Common SubsequenceMedium1147Longest Chunked Palindrome DecompositionHard1154Day of the YearEasy1156Swap For Longest Repeated Character SubstringMedium1160Find Words That Can Be Formed by CharactersEasy1163Last Substring in Lexicographical OrderHard1169Invalid TransactionsMedium1170Compare Strings by Frequency of the Smallest CharacterMedium1177Can Make Palindrome from SubstringMedium1178Number of Valid Words for Each PuzzleHard1189Maximum Number of BalloonsEasy1190Reverse Substrings Between Each Pair of ParenthesesMedium1202Smallest String With SwapsMedium1208Get Equal Substrings Within BudgetMedium1209Remove All Adjacent Duplicates in String IIMedium1221Split a String in Balanced StringsEasy1233Remove Sub-Folders from the FilesystemMedium1234Replace the Substring for Balanced StringMedium1239Maximum Length of a Concatenated String with Unique CharactersMedium1247Minimum Swaps to Make Strings EqualMedium1249Minimum Remove to Make Valid ParenthesesMedium1255Maximum Score Words Formed by LettersHard1268Search Suggestions SystemMedium1278Palindrome Partitioning IIIHard1286Iterator for CombinationMedium1297Maximum Number of Occurrences of a SubstringMedium1307Verbal Arithmetic PuzzleHard1309Decrypt String from Alphabet to Integer MappingEasy1312Minimum Insertion Steps to Make a String PalindromeHard1316Distinct Echo SubstringsHard1320Minimum Distance to Type a Word Using Two FingersHard1324Print Words VerticallyMedium1328Break a PalindromeMedium1332Remove Palindromic SubsequencesEasy1347Minimum Number of Steps to Make Two Strings AnagramMedium1358Number of Substrings Containing All Three CharactersMedium1360Number of Days Between Two DatesEasy1366Rank Teams by VotesMedium1370Increasing Decreasing StringEasy1371Find the Longest Substring Containing Vowels in Even CountsMedium1374Generate a String With Characters That Have Odd CountsEasy1392Longest Happy PrefixHard1396Design Underground SystemMedium1397Find All Good StringsHard1400Construct K Palindrome StringsMedium1404Number of Steps to Reduce a Number in Binary Representation to OneMedium1405Longest Happy StringMedium1408String Matching in an ArrayEasy1410HTML Entity ParserMedium1415The k-th Lexicographical String of All Happy Strings of Length nMedium1416Restore The ArrayHard1417Reformat The StringEasy1418Display Table of Food Orders in a RestaurantMedium1419Minimum Number of Frogs CroakingMedium1422Maximum Score After Splitting a StringEasy1433Check If a String Can Break Another StringMedium1436Destination CityEasy1446Consecutive CharactersEasy1447Simplified FractionsMedium1451Rearrange Words in a SentenceMedium1452People Whose List of Favorite Companies Is Not a Subset of Another ListMedium1455Check If a Word Occurs As a Prefix of Any Word in a SentenceEasy1456Maximum Number of Vowels in a Substring of Given LengthMedium1461Check If a String Contains All Binary Codes of Size KMedium1487Making File Names UniqueMedium1496Path CrossingEasy1505Minimum Possible Integer After at Most K Adjacent Swaps On DigitsHard1507Reformat DateEasy1513Number of Substrings With Only 1sMedium1520Maximum Number of Non-Overlapping SubstringsHard1525Number of Good Ways to Split a StringMedium1528Shuffle StringEasy1529Minimum Suffix FlipsMedium1531String Compression IIHard1540Can Convert String in K MovesMedium1541Minimum Insertions to Balance a Parentheses StringMedium1542Find Longest Awesome SubstringHard1544Make The String GreatEasy1545Find Kth Bit in Nth Binary StringMedium1556Thousand SeparatorEasy1573Number of Ways to Split a StringMedium1576Replace All ?'s to Avoid Consecutive Repeating CharactersEasy1578Minimum Time to Make Rope ColorfulMedium1585Check If String Is Transformable With Substring Sort OperationsHard1592Rearrange Spaces Between WordsEasy1593Split a String Into the Max Number of Unique SubstringsMedium1598Crawler Log FolderEasy1604Alert Using Same Key-Card Three or More Times in a One Hour PeriodMedium1614Maximum Nesting Depth of the ParenthesesEasy1616Split Two Strings to Make PalindromeMedium1624Largest Substring Between Two Equal CharactersEasy1625Lexicographically Smallest String After Applying OperationsMedium1629Slowest KeyEasy1638Count Substrings That Differ by One CharacterMedium1639Number of Ways to Form a Target String Given a DictionaryHard1647Minimum Deletions to Make Character Frequencies UniqueMedium1653Minimum Deletions to Make String BalancedMedium1657Determine if Two Strings Are CloseMedium1662Check If Two String Arrays are EquivalentEasy1663Smallest String With A Given Numeric ValueMedium1668Maximum Repeating SubstringEasy1678Goal Parser InterpretationEasy1684Count the Number of Consistent StringsEasy1689Partitioning Into Minimum Number Of Deci-Binary NumbersMedium1694Reformat Phone NumberEasy1702Maximum Binary String After ChangeMedium1704Determine if String Halves Are AlikeEasy1717Maximum Score From Removing SubstringsMedium1736Latest Time by Replacing Hidden DigitsEasy1737Change Minimum Characters to Satisfy One of Three ConditionsMedium1745Palindrome Partitioning IVHard1750Minimum Length of String After Deleting Similar EndsMedium1754Largest Merge Of Two StringsMedium1758Minimum Changes To Make Alternating Binary StringEasy1759Count Number of Homogenous SubstringsMedium1763Longest Nice SubstringEasy1768Merge Strings AlternatelyEasy1769Minimum Number of Operations to Move All Balls to Each BoxMedium1771Maximize Palindrome Length From SubsequencesHard1773Count Items Matching a RuleEasy1781Sum of Beauty of All SubstringsMedium1784Check if Binary String Has at Most One Segment of OnesEasy1790Check if One String Swap Can Make Strings EqualEasy1796Second Largest Digit in a StringEasy1805Number of Different Integers in a StringEasy1807Evaluate the Bracket Pairs of a StringMedium1812Determine Color of a Chessboard SquareEasy1813Sentence Similarity IIIMedium1816Truncate SentenceEasy1830Minimum Number of Operations to Make String SortedHard1832Check if the Sentence Is PangramEasy1839Longest Substring Of All Vowels in OrderMedium1844Replace All Digits with CharactersEasy1849Splitting a String Into Descending Consecutive ValuesMedium1850Minimum Adjacent Swaps to Reach the Kth Smallest NumberMedium1859Sorting the SentenceEasy1864Minimum Number of Swaps to Make the Binary String AlternatingMedium1869Longer Contiguous Segments of Ones than ZerosEasy1871Jump Game VIIMedium1876Substrings of Size Three with Distinct CharactersEasy1880Check if Word Equals Summation of Two WordsEasy1881Maximum Value after InsertionMedium1888Minimum Number of Flips to Make the Binary String AlternatingMedium1896Minimum Cost to Change the Final Value of ExpressionHard1897Redistribute Characters to Make All Strings EqualEasy1898Maximum Number of Removable CharactersMedium1903Largest Odd Number in StringEasy1904The Number of Full Rounds You Have PlayedMedium1910Remove All Occurrences of a SubstringMedium1915Number of Wonderful SubstringsMedium1927Sum GameMedium1930Unique Length-3 Palindromic SubsequencesMedium1935Maximum Number of Words You Can TypeEasy1941Check if All Characters Have Equal Number of OccurrencesEasy1945Sum of Digits of String After ConvertEasy1946Largest Number After Mutating SubstringMedium1948Delete Duplicate Folders in SystemHard1957Delete Characters to Make Fancy StringEasy1960Maximum Product of the Length of Two Palindromic SubstringsHard1961Check If String Is a Prefix of ArrayEasy1963Minimum Number of Swaps to Make the String BalancedMedium1967Number of Strings That Appear as Substrings in WordEasy1974Minimum Time to Type Word Using Special TypewriterEasy1977Number of Ways to Separate NumbersHard1980Find Unique Binary StringMedium1985Find the Kth Largest Integer in the ArrayMedium1987Number of Unique Good SubsequencesHard2000Reverse Prefix of WordEasy2002Maximum Product of the Length of Two Palindromic SubsequencesMedium2011Final Value of Variable After Performing OperationsEasy2014Longest Subsequence Repeated k TimesHard2019The Score of Students Solving Math ExpressionHard2023Number of Pairs of Strings With Concatenation Equal to TargetMedium2024Maximize the Confusion of an ExamMedium2027Minimum Moves to Convert StringEasy2030Smallest K-Length Subsequence With Occurrences of a LetterHard2038Remove Colored Pieces if Both Neighbors are the Same ColorMedium2042Check if Numbers Are Ascending in a SentenceEasy2047Number of Valid Words in a SentenceEasy2053Kth Distinct String in an ArrayEasy2055Plates Between CandlesMedium2056Number of Valid Move Combinations On ChessboardHard2060Check if an Original String Exists Given Two Encoded StringsHard2062Count Vowel Substrings of a StringEasy2063Vowels of All SubstringsMedium2068Check Whether Two Strings are Almost EquivalentEasy2075Decode the Slanted CiphertextMedium2085Count Common Words With One OccurrenceEasy2086Minimum Number of Food Buckets to Feed the HamstersMedium2096Step-By-Step Directions From a Binary Tree Node to AnotherMedium2103Rings and RodsEasy2108Find First Palindromic String in the ArrayEasy2109Adding Spaces to a StringMedium2114Maximum Number of Words Found in SentencesEasy2115Find All Possible Recipes from Given SuppliesMedium2116Check if a Parentheses String Can Be ValidMedium2120Execution of All Suffix Instructions Staying in a GridMedium2124Check if All A's Appears Before All B'sEasy2125Number of Laser Beams in a BankMedium2129Capitalize the TitleEasy2131Longest Palindrome by Concatenating Two Letter WordsMedium2135Count Words Obtained After Adding a LetterMedium2138Divide a String Into Groups of Size kEasy2147Number of Ways to Divide a Long CorridorHard2156Find Substring With Given Hash ValueHard2157Groups of StringsHard2166Design BitsetMedium2167Minimum Time to Remove All Cars Containing Illegal GoodsHard2182Construct String With Repeat LimitMedium2185Counting Words With a Given PrefixEasy2186Minimum Number of Steps to Make Two Strings Anagram IIMedium2193Minimum Number of Moves to Make PalindromeHard2194Cells in a Range on an Excel SheetEasy2207Maximize Number of Subsequences in a StringMedium2209Minimum White Tiles After Covering With CarpetsHard2211Count Collisions on a RoadMedium2213Longest Substring of One Repeating CharacterHard2222Number of Ways to Select BuildingsMedium2223Sum of Scores of Built StringsHard2224Minimum Number of Operations to Convert TimeEasy2227Encrypt and Decrypt StringsHard2232Minimize Result by Adding Parentheses to ExpressionMedium2243Calculate Digit Sum of a StringEasy2246Longest Path With Different Adjacent CharactersHard2255Count Prefixes of a Given StringEasy2259Remove Digit From Number to Maximize ResultEasy2262Total Appeal of A StringHard2264Largest 3-Same-Digit Number in StringEasy2266Count Number of TextsMedium2269Find the K-Beauty of a NumberEasy2273Find Resultant Array After Removing AnagramsEasy2278Percentage of Letter in StringEasy2283Check if Number Has Equal Digit Count and Digit ValueEasy2284Sender With Largest Word CountMedium2287Rearrange Characters to Make Target StringEasy2288Apply Discount to PricesMedium2296Design a Text EditorHard2299Strong Password Checker IIEasy2301Match Substring After ReplacementHard2306Naming a CompanyHard2309Greatest English Letter in Upper and Lower CaseEasy2311Longest Binary Subsequence Less Than or Equal to KMedium2315Count AsterisksEasy2325Decode the MessageEasy2337Move Pieces to Obtain a StringMedium2343Query Kth Smallest Trimmed NumberMedium2351First Letter to Appear TwiceEasy2353Design a Food Rating SystemMedium2370Longest Ideal SubsequenceMedium2375Construct Smallest Number From DI StringMedium2379Minimum Recolors to Get K Consecutive Black BlocksEasy2380Time Needed to Rearrange a Binary StringMedium2381Shifting Letters IIMedium2384Largest Palindromic NumberMedium2390Removing Stars From a StringMedium2391Minimum Amount of Time to Collect GarbageMedium2399Check Distances Between Same LettersEasy2405Optimal Partition of StringMedium2409Count Days Spent TogetherEasy2414Length of the Longest Alphabetical Continuous SubstringMedium2416Sum of Prefix Scores of StringsHard2418Sort the PeopleEasy2423Remove Letter To Equalize FrequencyEasy2430Maximum Deletions on a StringHard2434Using a Robot to Print the Lexicographically Smallest StringMedium2437Number of Valid Clock TimesEasy2446Determine if Two Events Have ConflictEasy2451Odd String DifferenceEasy2452Words Within Two Edits of DictionaryMedium2456Most Popular Video CreatorMedium2468Split Message Based on LimitHard2472Maximum Number of Non-overlapping Palindrome SubstringsHard2478Number of Beautiful PartitionsHard2483Minimum Penalty for a ShopMedium2484Count Palindromic SubsequencesHard2486Append Characters to String to Make SubsequenceMedium2490Circular SentenceEasy2496Maximum Value of a String in an ArrayEasy2506Count Pairs Of Similar StringsEasy2512Reward Top K StudentsMedium2514Count AnagramsHard2515Shortest Distance to Target String in a Circular ArrayEasy2516Take K of Each Character From Left and RightMedium2522Partition String Into Substrings With Values at Most KMedium2531Make Number of Distinct Characters EqualMedium2546Apply Bitwise Operations to Make Strings EqualMedium2559Count Vowel Strings in RangesMedium2564Substring XOR QueriesMedium2565Subsequence With the Minimum ScoreHard2573Find the String with LCPHard2575Find the Divisibility Array of a StringMedium2586Count the Number of Vowel Strings in RangeEasy2606Find the Substring With Maximum CostMedium2609Find the Longest Balanced Substring of a Binary StringEasy2645Minimum Additions to Make Valid StringMedium2663Lexicographically Smallest Beautiful StringHard2678Number of Senior CitizensEasy2696Minimum String Length After Removing SubstringsEasy2697Lexicographically Smallest PalindromeEasy2707Extra Characters in a StringMedium2710Remove Trailing Zeros From a StringEasy2712Minimum Cost to Make All Characters EqualMedium2716Minimize String LengthEasy2719Count of IntegersHard2730Find the Longest Semi-Repetitive SubstringMedium2734Lexicographically Smallest String After Substring OperationMedium2744Find Maximum Number of String PairsEasy2746Decremental String ConcatenationMedium2767Partition String Into Minimum Beautiful SubstringsMedium2781Length of the Longest Valid SubstringHard2785Sort Vowels in a StringMedium2788Split Strings by SeparatorEasy2800Shortest String That Contains Three StringsMedium2801Count Stepping Numbers in RangeHard2810Faulty KeyboardEasy2825Make String a Subsequence Using Cyclic IncrementsMedium2828Check if a String Is an Acronym of WordsEasy2833Furthest Point From OriginEasy2839Check if Strings Can be Made Equal With Operations IEasy2840Check if Strings Can be Made Equal With Operations IIMedium2842Count K-Subsequences of a String With Maximum BeautyHard2844Minimum Operations to Make a Special NumberMedium2851String TransformationHard2864Maximum Odd Binary NumberEasy2896Apply Operations to Make Two Strings EqualMedium2900Longest Unequal Adjacent Groups Subsequence IEasy2901Longest Unequal Adjacent Groups Subsequence IIMedium2904Shortest and Lexicographically Smallest Beautiful StringMedium2911Minimum Changes to Make K Semi-palindromesHard2914Minimum Number of Changes to Make Binary String BeautifulMedium2933High-Access EmployeesMedium2937Make Three Strings EqualEasy2938Separate Black and White BallsMedium2942Find Words Containing CharacterEasy2947Count Beautiful Substrings IMedium2949Count Beautiful Substrings IIHard2953Count Complete SubstringsHard2957Remove Adjacent Almost-Equal CharactersMedium2976Minimum Cost to Convert String IMedium2977Minimum Cost to Convert String IIHard2981Find Longest Special Substring That Occurs Thrice IMedium2982Find Longest Special Substring That Occurs Thrice IIMedium2983Palindrome Rearrangement QueriesHard2999Count the Number of Powerful IntegersHard3003Maximize the Number of Partitions After OperationsHard3006Find Beautiful Indices in the Given Array IMedium3008Find Beautiful Indices in the Given Array IIHard3014Minimum Number of Pushes to Type Word IEasy3016Minimum Number of Pushes to Type Word IIMedium3019Number of Changing KeysEasy3029Minimum Time to Revert Word to Initial State IMedium3031Minimum Time to Revert Word to Initial State IIHard3035Maximum Palindromes After OperationsMedium3042Count Prefix and Suffix Pairs IEasy3043Find the Length of the Longest Common PrefixMedium3045Count Prefix and Suffix Pairs IIHard3076Shortest Uncommon Substring in an ArrayMedium3081Replace Question Marks in String to Minimize Its ValueMedium3083Existence of a Substring in a String and Its ReverseEasy3084Count Substrings Starting and Ending with Given CharacterMedium3085Minimum Deletions to Make String K-SpecialMedium3090Maximum Length Substring With Two OccurrencesEasy3093Longest Common Suffix QueriesHard3106Lexicographically Smallest String After Operations With ConstraintMedium3110Score of a StringEasy3114Latest Time You Can Obtain After Replacing CharactersEasy3120Count the Number of Special Characters IEasy3121Count the Number of Special Characters IIMedium3136Valid WordEasy3137Minimum Number of Operations to Make Word K-PeriodicMedium3138Minimum Length of Anagram ConcatenationMedium3143Maximum Points Inside the SquareMedium3144Minimum Substring Partition of Equal Character FrequencyMedium3146Permutation Difference between Two StringsEasy3163String Compression IIIMedium3168Minimum Number of Chairs in a Waiting RoomEasy3170Lexicographically Minimum String After Removing StarsMedium3174Clear DigitsEasy3210Find the Encrypted StringEasy3211Generate Binary Strings Without Adjacent ZerosMedium3213Construct String with Minimum CostHard3216Lexicographically Smallest String After a SwapEasy3223Minimum Length of String After OperationsMedium3227Vowels Game in a StringMedium3228Maximum Number of Operations to Move Ones to the EndMedium3234Count the Number of Substrings With Dominant OnesMedium3248Snake in MatrixEasy3258Count Substrings That Satisfy K-Constraint IEasy3260Find the Largest Palindrome Divisible by KHard3261Count Substrings That Satisfy K-Constraint IIHard3271Hash Divided StringMedium3274Check if Two Chessboard Squares Have the Same ColorEasy3280Convert Date to BinaryEasy3291Minimum Number of Valid Strings to Form Target IMedium3292Minimum Number of Valid Strings to Form Target IIHard3295Report Spam MessageMedium3297Count Substrings That Can Be Rearranged to Contain a String IMedium3298Count Substrings That Can Be Rearranged to Contain a String IIHard3302Find the Lexicographically Smallest Valid SequenceMedium3303Find the Occurrence of First Almost Equal SubstringHard3305Count of Substrings Containing Every Vowel and K Consonants IMedium3306Count of Substrings Containing Every Vowel and K Consonants IIMedium3316Find Maximum Removals From Source StringMedium3320Count The Number of Winning SequencesHard3324Find the Sequence of Strings Appeared on the ScreenMedium3325Count Substrings With K-Frequency Characters IMedium3327Check if DFS Strings Are PalindromesHard3330Find the Original Typed String IEasy3331Find Subtree Sizes After ChangesMedium3333Find the Original Typed String IIHard3335Total Characters in String After Transformations IMedium3337Total Characters in String After Transformations IIHard3340Check Balanced StringEasy3343Count Number of Balanced PermutationsHard3348Smallest Divisible Digit Product IIHard3352Count K-Reducible Numbers Less Than NHard3361Shift Distance Between Two StringsMedium3365Rearrange K Substrings to Form Target StringMedium3387Maximize Amount After Two Days of ConversionsMedium3389Minimum Operations to Make Character Frequencies EqualHard3399Smallest Substring With Identical Characters IIHard3403Find the Lexicographically Largest String From the Box IMedium3407Substring Matching PatternEasy3412Find Mirror Score of a StringMedium3435Frequencies of Shortest SupersequencesHard3438Find Valid Pair of Adjacent Digits in StringEasy3441Minimum Cost Good CaptionHard3442Maximum Difference Between Even and Odd Frequency IEasy3443Maximum Manhattan Distance After K ChangesMedium3445Maximum Difference Between Even and Odd Frequency IIHard3448Count Substrings Divisible By Last DigitHard3455Shortest Matching SubstringHard3456Find Special Substring of Length KEasy3458Select K Disjoint Special SubstringsMedium3461Check If Digits Are Equal in String After Operations IEasy3463Check If Digits Are Equal in String After Operations IIHard3472Longest Palindromic Subsequence After at Most K OperationsMedium3474Lexicographically Smallest Generated StringHard3484Design SpreadsheetMedium3485Longest Common Prefix of K Strings After RemovalHard3498Reverse Degree of a StringEasy3499Maximize Active Section with Trade IMedium3501Maximize Active Section with Trade IIHard3503Longest Palindrome After Substring Concatenation IMedium3504Longest Palindrome After Substring Concatenation IIHard3517Smallest Palindromic Rearrangement IMedium3518Smallest Palindromic Rearrangement IIHard3519Count Numbers with Non-Decreasing Digits Hard3522Calculate Score After Performing InstructionsMedium3527Find the Most Common ResponseMedium3529Count Cells in Overlapping Horizontal and Vertical SubstringsMedium3541Find Most Frequent Vowel and ConsonantEasy3545Minimum Deletions for At Most K Distinct CharactersEasy3556Sum of Largest Prime SubstringsMedium3557Find Maximum Number of Non Intersecting SubstringsMedium3561Resulting String After Adjacent RemovalsMedium3563Lexicographically Smallest String After Adjacent RemovalsHard3579Minimum Steps to Convert String with OperationsHard3582Generate Tag for Video CaptionEasy3597Partition String Medium3598Longest Common Prefix Between Adjacent Strings After RemovalsMedium3602Hexadecimal and Hexatrigesimal ConversionEasy3606Coupon Code ValidatorEasy3612Process String with Special Operations IMedium3614Process String with Special Operations IIHard3615Longest Palindromic Path in GraphHard
← Browse all LeetCode problems
PhantomCodeAIPhantomCodeAI
PhantomCodeAI is an undetectable desktop application to help you pass your Leetcode interviews.
All systems online
Download

Legal

Refund PolicyTerms of ServiceCancellation PolicyPrivacy Policy

Pages

Contact SupportHelp CenterInstant SupportFAQBlogFeaturesInterview CopilotCoding CopilotInterview QuestionsPricingMock Interview PricingEarn with UsBest AI Interview Assistants 2026FeedbackLeetcode ProblemsLoginCreate Account

Compare

All 29 comparisons →Why switch (29 alternatives) →Interview Coder AlternativeFinal Round AI AlternativeUltraCode AI AlternativeParakeet AI AlternativeAI Apply AlternativeCoderRank AlternativeInterviewing.io AlternativeShadeCoder Alternative

Resources

Salary GuideResume TemplatesWhat Is PhantomCodeAIIs PhantomCodeAI Detectable?Use PhantomCodeAI in HackerRankvs LeetCode PremiumFor European EngineersFor FAANG Interview PrepPost-Layoff ComebackIndia Pricing (INR)

Interview Types

Coding InterviewSystem Design InterviewDSA InterviewLeetCode InterviewAlgorithms InterviewData Structure InterviewSQL InterviewOnline Assessment

Interview Questions

See all →
GoogleAmazonMetaMicrosoftAppleNetflixStripeUberAirbnbBloombergSoftware EngineerFrontend EngineerBackend EngineerData EngineerML EngineerDevOps EngineerData ScientistEngineering ManagerBehavioralSystem Design

Mock Interview by Round Type

All formats →
Mock Interview HubMock Coding InterviewMock Behavioral InterviewMock System Design

AI for Industry Interviews

All industries →
Sales InterviewsPM InterviewsFinance InterviewsConsulting InterviewsDesign Interviews

Coding Interview Patterns

See all patterns →
Coding Interviews HubDynamic ProgrammingTwo Pointers + Sliding WindowGraph AlgorithmsTree AlgorithmsBinary Search

Interview Guides

See all guides →
How to Ace an InterviewHow to Crack InterviewsBest Interview AnswersScreening Interview QuestionsTelephone Interview TipsWorking Interview ExplainedCracking the PM InterviewFAANG 30-Day RoadmapTop 10 LeetCode PatternsSystem Design Prep GuideSTAR Behavioral MethodBehavioral Interview Qs

Alternatives — why engineers switch

See all 29 →
Interview CoderFinal Round AIParakeet AILockedIn AIUltraCode AIShadeCoderSensei AIVerve AICluelyChatGPTBeyz AIInterview SidekickYoodliAlgoMonsterCoderRankExponentFormationInterviewing.ioInterview CakeBig InterviewInterview KickstartPrampScalerAI ApplyCareerflowJobscanKickresumeTeal HQHireVue

AI Interview Tools

AI Interview AssistantAI Interview CoachAI for Job InterviewsAI Interview Preparation ToolReal-Time AI Interview AnswersInterview AI HelperReal-Time AI Interview AssistantAI Interview BotBest AI Interview Tools 2026AI Interview QuestionsPractice Interview QuestionsAI to Answer Interview QuestionsAI Phone Interview HelpAI Interviewing SoftwareAI Interview HubInterview CopilotAI Coding Interview AssistantMock Interview

© 2026 PhantomCodeAI. All rights reserved.