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Coding problems

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

Bracket BalanceStack · StringEasyLongest Balanced Bracket StretchStack · String · Dynamic ProgrammingHardWater Between WallsStack · Array · Two PointersHardTidy a Folder RouteStack · StringMediumBiggest Rectangle Under the SkylineStack · Array · Monotonic StackHardBiggest Solid Panel BlockStack · Array · Dynamic ProgrammingHardLeft, Node, RightStack · Tree · Depth-First SearchEasyTree Into a Right ChainStack · Tree · Depth-First SearchMediumList Folded From Both EndsStack · Recursion · Linked ListMediumParent Before ChildrenStack · Tree · Depth-First SearchEasyChildren Before ParentStack · Tree · Depth-First SearchEasyPostfix CalculatorStack · Array · MathMediumPlus-Minus Calculator With BracketsStack · Recursion · MathHardFour-Operation CalculatorStack · Math · StringMediumSymmetric Bead StringStack · Recursion · Linked ListEasyPreorder of a Search TreeStack · Tree · Binary Search TreeMediumK Keys Nearest to a TargetStack · Tree · Depth-First SearchHardEvery Letter OnceStack · Greedy · StringMediumLargest Number From Two RowsStack · Greedy · ArrayHardChecking a Tree Record With Hash MarksStack · Tree · StringMediumLongest Path to a FileStack · Depth-First Search · StringMediumExpand Repeat BracketsStack · Recursion · StringMediumErase Digits for the Smallest NumberStack · Greedy · StringMediumEvaluating Nested ConditionsStack · Recursion · StringMediumForward Digit List SumStack · Linked List · MathMediumLow, Peak, MiddleStack · Array · Binary SearchMediumSmallest Up-Down SequenceStack · Greedy · ArrayMediumClear the Marble RowStack · Breadth-First Search · MemoizationHardNext Larger on the RightStack · Array · Hash TableEasyNext Larger Around the CircleStack · Array · Monotonic StackMediumTree From Bracket NotationStack · Tree · Depth-First SearchMediumFix the Middle of the LineStack · Greedy · ArrayMediumMarkup Snippet CheckStack · StringHardOwn Time per FunctionStack · ArrayMediumPeak-Split TreeStack · Tree · ArrayMediumBrackets With WildcardsStack · Greedy · StringMediumQuiz Score LogStack · Array · SimulationEasyElement Tally From a FormulaStack · Hash Table · StringHardRobots Clashing on a RailStack · Array · SimulationMediumA Calculator With Brackets and VariablesStack · Recursion · Hash TableHardWaiting for a Higher PriceStack · Array · Monotonic StackMediumSorting Batches With RepeatsStack · Greedy · ArrayHardMost Pieces Sorted SeparatelyStack · Greedy · ArrayMediumSimplify a Letter PolynomialStack · Recursion · Hash TableHardCalculator With Brackets and Four OperationsStack · Recursion · MathHardSame Text After ErasingStack · Two Pointers · StringEasyConvoys at the FinishStack · Array · SortingMediumWorth of Nested BracketsStack · StringMediumLetter on a Self-Copying TapeStack · StringMediumSearch Tree Into a LineStack · Tree · Depth-First SearchEasy
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