Coding problems

Algorithm problems with tests in Python, JavaScript, Java, Go and C++, checked on our server.

Pair With a Target SumArray · Hash TableEasy Longest Repeat-Free StretchHash Table · String · Sliding WindowMedium Number in Roman NumeralsHash Table · Math · StringMedium Value of a Roman NumeralHash Table · Math · StringEasy Keypad WordsHash Table · String · BacktrackingMedium Word Blocks in Any OrderHash Table · String · Sliding WindowHard Sudoku Board Without ClashesArray · Hash Table · MatrixMedium Complete the SudokuArray · Hash Table · BacktrackingHard Smallest Absent PositiveArray · Hash TableHard Anagram BucketsArray · Hash Table · StringMedium Zero Out the CrossesArray · Hash Table · MatrixMedium Shortest Covering WindowHash Table · String · Sliding WindowHard Tree From Pre-Order and In-Order WalksTree · Array · Hash TableMedium Tree From In-Order and Post-Order WalksTree · Array · Hash TableMedium One Letter at a TimeBreadth-First Search · Hash Table · StringHard Longest Unbroken RunUnion Find · Array · Hash TableMedium Split Into Dictionary WordsTrie · Memoization · ArrayMedium Every Way to Space the WordsTrie · Memoization · ArrayHard Stars on One Straight LineGeometry · Array · Hash TableHard Two-Letter StretchHash Table · String · Sliding WindowMedium Fraction as a DecimalHash Table · Math · StringMedium The Candidate With Most VotesArray · Hash Table · Divide and ConquerEasy Recurring Gene WindowsBit Manipulation · Hash Table · StringMedium Digit Squares Down to OneHash Table · Math · Two PointersEasy Same Letter CipherHash Table · StringEasy Does Any Value RepeatArray · Hash Table · SortingEasy Repeat Within ReachArray · Hash Table · Sliding WindowEasy More Than a Third of the VotesArray · Hash Table · CountingMedium Same Letters, ReshuffledHash Table · String · SortingEasy Same When FlippedHash Table · Two Pointers · StringEasy Words Equal Up to a ShiftArray · Hash Table · StringMedium Numbers Made of Twos, Threes and FivesHash Table · Math · Dynamic ProgrammingMedium Shuffle Into a PalindromeBit Manipulation · Hash Table · StringEasy Palindromes From a Set of LettersHash Table · String · BacktrackingMedium The Lost TicketBit Manipulation · Array · Hash TableEasy Words Following a Letter PatternHash Table · StringEasy Does the String Fit the Letter TemplateHash Table · String · BacktrackingMedium A Hint for a Digit GuessHash Table · String · CountingMedium Islands After Each LandfillUnion Find · Array · Hash TableHard Multiply Mostly-Zero MatricesArray · Hash Table · MatrixMedium Tree Columns, Top DownTree · Depth-First Search · Breadth-First SearchMedium Longest Run with a Given SumArray · Hash Table · Prefix SumMedium Glued Into a PalindromeTrie · Array · Hash TableHard Window with Few Kinds of LettersHash Table · String · Sliding WindowMedium Most Common ValuesArray · Hash Table · Divide and ConquerMedium Values in Both ListsArray · Hash Table · Two PointersEasy Shared Values With RepeatsArray · Hash Table · Two PointersEasy Vertical Mirror LineArray · Hash Table · MathMedium Equal Letters Kept ApartGreedy · Hash Table · StringHard Note From Clipped LettersHash Table · String · CountingEasy

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