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    Remove BracketsNot Completed

    Solutions: 132 | View user solutions | Added 08/23/17

    Plus MinusNot Completed

    Solutions: 43 | View user solutions | Added 08/04/17

    Wildcard CharactersNot Completed

    Solutions: 34 | View user solutions | Added 07/22/17

    You have access to 10 free challenges and solutions below

    Easy Difficulty

    First ReverseNot Completed

    Solutions: 82366 | Step-by-step solution | Challenge discussion

    First FactorialNot Completed

    Solutions: 56604 | Step-by-step solution | Challenge discussion

    Longest WordNot Completed

    Solutions: 42922 | Step-by-step solution | Challenge discussion

    Letter ChangesNot Completed

    Solutions: 45780 | Step-by-step solution | Challenge discussion

    Simple AddingNot Completed

    Solutions: 37807 | Step-by-step solution | Challenge discussion

    Letter CapitalizeNot Completed

    Solutions: 32191 | Step-by-step solution | Challenge discussion

    Simple SymbolsNot Completed

    Solutions: 25776 | Step-by-step solution | Challenge discussion

    Check NumsNot Completed

    Solutions: 27217 | Step-by-step solution | Challenge discussion

    Time ConvertNot Completed

    Solutions: 20605 | Step-by-step solution | Challenge discussion

    Alphabet SoupNot Completed

    Solutions: 19340 | Step-by-step solution | Challenge discussion

    AB CheckNot Completed

    Solutions: 15641 | Step-by-step solution | Challenge discussion

    Vowel CountNot Completed

    Solutions: 14672 | Step-by-step solution | Challenge discussion

    Word CountNot Completed

    Solutions: 13846 | Step-by-step solution | Challenge discussion

    Ex OhNot Completed

    Solutions: 13413 | Step-by-step solution | Challenge discussion

    PalindromeNot Completed

    Solutions: 15589 | Step-by-step solution | Challenge discussion

    Arith GeoNot Completed

    Solutions: 12342 | Step-by-step solution | Challenge discussion

    Array Addition INot Completed

    Solutions: 7728 | Step-by-step solution | Challenge discussion

    Letter Count INot Completed

    Solutions: 7097 | Step-by-step solution | Challenge discussion

    Second GreatLowNot Completed

    Solutions: 11891 | Step-by-step solution | Challenge discussion

    Division StringifiedNot Completed

    Solutions: 8926 | Step-by-step solution | Challenge discussion

    Counting Minutes INot Completed

    Solutions: 5276 | Step-by-step solution | Challenge discussion

    Mean ModeNot Completed

    Solutions: 6992 | Step-by-step solution | Challenge discussion

    Dash InsertNot Completed

    Solutions: 7894 | Step-by-step solution | Challenge discussion

    Swap CaseNot Completed

    Solutions: 7603 | Step-by-step solution | Challenge discussion

    Number AdditionNot Completed

    Solutions: 7336 | Step-by-step solution | Challenge discussion

    Third GreatestNot Completed

    Solutions: 6806 | Step-by-step solution | Challenge discussion

    Powers of TwoNot Completed

    Solutions: 7676 | Step-by-step solution | Challenge discussion

    Additive PersistenceNot Completed

    Solutions: 5333 | Step-by-step solution | Challenge discussion

    Multiplicative PersistenceNot Completed

    Solutions: 4151 | Step-by-step solution | Challenge discussion

    Off Line MinimumNot Completed

    Solutions: 5545 | Step-by-step solution | Challenge discussion

    Changing SequenceNot Completed

    Solutions: 2028 | Step-by-step solution | Challenge discussion

    Overlapping RangesNot Completed

    Solutions: 2040 | Step-by-step solution | Challenge discussion

    SuperincreasingNot Completed

    Solutions: 2045 | Step-by-step solution | Challenge discussion

    Hamming DistanceNot Completed

    Solutions: 1389 | Step-by-step solution | Challenge discussion

    Rectangle AreaNot Completed

    Solutions: 1683 | Step-by-step solution | Challenge discussion

    Bitwise OneNot Completed

    Solutions: 1369 | Step-by-step solution | Challenge discussion

    Other ProductsNot Completed

    Solutions: 1363 | Step-by-step solution | Challenge discussion

    Wave SortingNot Completed

    Solutions: 860 | Step-by-step solution | Challenge discussion

    Array MatchingNot Completed

    Solutions: 1020 | Step-by-step solution | Challenge discussion

    Binary ReversalNot Completed

    Solutions: 862 | Step-by-step solution | Challenge discussion

    Longest Increasing SequenceNot Completed

    Solutions: 814 | Step-by-step solution | Challenge discussion

    Even PairsNot Completed

    Solutions: 773 | Step-by-step solution | Challenge discussion

    Next PalindromeNot Completed

    Solutions: 699 | Step-by-step solution | Challenge discussion

    Largest PairNot Completed

    Solutions: 1028 | Step-by-step solution | Challenge discussion

    Nonrepeating CharacterNot Completed

    Solutions: 709 | Step-by-step solution | Challenge discussion

    Two SumNot Completed

    Solutions: 1237 | Step-by-step solution | Challenge discussion

    Bitwise TwoNot Completed

    Solutions: 494 | Step-by-step solution | Challenge discussion

    Power Set CountNot Completed

    Solutions: 784 | Step-by-step solution | Challenge discussion

    Product DigitsNot Completed

    Solutions: 1026 | Step-by-step solution | Challenge discussion

    Palindrome CreatorNot Completed

    Solutions: 753 | Step-by-step solution | Challenge discussion

    Basic Roman NumeralsNot Completed

    Solutions: 511 | Step-by-step solution | Challenge discussion

    Food DistributionNot Completed

    Solutions: 397 | Step-by-step solution | Challenge discussion

    Three SumNot Completed

    Solutions: 495 | Step-by-step solution | Challenge discussion

    Correct PathNot Completed

    Solutions: 260 | Step-by-step solution | Challenge discussion

    Scale BalancingNot Completed

    Solutions: 417 | Step-by-step solution | Challenge discussion

    Three NumbersNot Completed

    Solutions: 415 | Step-by-step solution | Challenge discussion

    Alphabet SearchingNot Completed

    Solutions: 395 | Step-by-step solution | Challenge discussion

    Time DifferenceNot Completed

    Solutions: 231 | Step-by-step solution | Challenge discussion

    Triangle RowNot Completed

    Solutions: 234 | Step-by-step solution | Challenge discussion

    Vowel SquareNot Completed

    Solutions: 284 | Step-by-step solution | Challenge discussion

    Closest EnemyNot Completed

    Solutions: 336 | Step-by-step solution | Challenge discussion

    Closest Enemy IINot Completed

    Solutions: 170 | Step-by-step solution | Challenge discussion

    Number StreamNot Completed

    Solutions: 186 | Step-by-step solution | Challenge discussion

    Largest FourNot Completed

    Solutions: 338 | Step-by-step solution | Challenge discussion

    Distinct CharactersNot Completed

    Solutions: 234 | Step-by-step solution | Challenge discussion

    Questions MarksNot Completed

    Solutions: 365 | Step-by-step solution | Challenge discussion

    Camel CaseNot Completed

    Solutions: 260 | Step-by-step solution | Challenge discussion

    ASCII ConversionNot Completed

    Solutions: 172 | Step-by-step solution | Challenge discussion

    Simple EvensNot Completed

    Solutions: 249 | Step-by-step solution | Challenge discussion

    Snake CaseNot Completed

    Solutions: 216 | Step-by-step solution | Challenge discussion

    Sum MultiplierNot Completed

    Solutions: 288 | Step-by-step solution | Challenge discussion

    String MergeNot Completed

    Solutions: 261 | Step-by-step solution | Challenge discussion

    One DecrementedNot Completed

    Solutions: 254 | Step-by-step solution | Challenge discussion

    Element MergerNot Completed

    Solutions: 267 | Step-by-step solution | Challenge discussion

    GCFNot Completed

    Solutions: 245 | Step-by-step solution | Challenge discussion

    Serial NumberNot Completed

    Solutions: 237 | Step-by-step solution | Challenge discussion

    String PeriodsNot Completed

    Solutions: 204 | Step-by-step solution | Challenge discussion

    Palindrome SwapperNot Completed

    Solutions: 121 | Step-by-step solution | Challenge discussion

    Remove BracketsNot Completed

    Solutions: 132 | Step-by-step solution | Challenge discussion

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    Medium Difficulty

    Prime TimeNot Completed

    Solutions: 11429 | Step-by-step solution | Challenge discussion

    Run Length Not Completed

    Solutions: 7969 | Step-by-step solution | Challenge discussion

    Prime MoverNot Completed

    Solutions: 7079 | Step-by-step solution | Challenge discussion

    Palindrome TwoNot Completed

    Solutions: 6672 | Step-by-step solution | Challenge discussion

    DivisionNot Completed

    Solutions: 6264 | Step-by-step solution | Challenge discussion

    String ScrambleNot Completed

    Solutions: 6756 | Step-by-step solution | Challenge discussion

    Arith Geo IINot Completed

    Solutions: 4709 | Step-by-step solution | Challenge discussion

    Array AdditionNot Completed

    Solutions: 3988 | Step-by-step solution | Challenge discussion

    Binary ConverterNot Completed

    Solutions: 4297 | Step-by-step solution | Challenge discussion

    Letter CountNot Completed

    Solutions: 4135 | Step-by-step solution | Challenge discussion

    Simple ModeNot Completed

    Solutions: 4696 | Step-by-step solution | Challenge discussion

    Caesar CipherNot Completed

    Solutions: 4759 | Step-by-step solution | Challenge discussion

    Formatted DivisionNot Completed

    Solutions: 3543 | Step-by-step solution | Challenge discussion

    ConsecutiveNot Completed

    Solutions: 3843 | Step-by-step solution | Challenge discussion

    Counting MinutesNot Completed

    Solutions: 2565 | View all user solutions | Challenge discussion

    Permutation StepNot Completed

    Solutions: 3064 | View all user solutions | Challenge discussion

    Prime CheckerNot Completed

    Solutions: 2330 | View all user solutions | Challenge discussion

    Dash Insert IINot Completed

    Solutions: 4629 | View all user solutions | Challenge discussion

    Swap IINot Completed

    Solutions: 2553 | View all user solutions | Challenge discussion

    Number SearchNot Completed

    Solutions: 3105 | View all user solutions | Challenge discussion

    Triple DoubleNot Completed

    Solutions: 2901 | View all user solutions | Challenge discussion

    Bracket MatcherNot Completed

    Solutions: 2649 | View all user solutions | Challenge discussion

    String ReductionNot Completed

    Solutions: 2183 | View all user solutions | Challenge discussion

    Coin DeterminerNot Completed

    Solutions: 2143 | View all user solutions | Challenge discussion

    ThreeFive MultiplesNot Completed

    Solutions: 2653 | View all user solutions | Challenge discussion

    Fibonacci CheckerNot Completed

    Solutions: 2494 | View all user solutions | Challenge discussion

    Multiple BracketsNot Completed

    Solutions: 2147 | View all user solutions | Challenge discussion

    Most Free TimeNot Completed

    Solutions: 1304 | View all user solutions | Challenge discussion

    Overlapping RectanglesNot Completed

    Solutions: 1483 | View all user solutions | Challenge discussion

    Distinct ListNot Completed

    Solutions: 2248 | View all user solutions | Challenge discussion

    Look Say SequenceNot Completed

    Solutions: 1341 | View all user solutions | Challenge discussion

    Number EncodingNot Completed

    Solutions: 1378 | View all user solutions | Challenge discussion

    Stock PickerNot Completed

    Solutions: 592 | View all user solutions | Challenge discussion

    Max SubarrayNot Completed

    Solutions: 499 | View all user solutions | Challenge discussion

    Missing DigitNot Completed

    Solutions: 336 | View all user solutions | Challenge discussion

    K Unique CharactersNot Completed

    Solutions: 331 | View all user solutions | Challenge discussion

    Bitmap HolesNot Completed

    Solutions: 240 | View all user solutions | Challenge discussion

    Symmetric TreeNot Completed

    Solutions: 208 | View all user solutions | Challenge discussion

    Binary Search Tree LCANot Completed

    Solutions: 185 | View all user solutions | Challenge discussion

    Binary Tree LCANot Completed

    Solutions: 104 | View all user solutions | Challenge discussion

    LRU CacheNot Completed

    Solutions: 120 | View all user solutions | Challenge discussion

    Tree ConstructorNot Completed

    Solutions: 112 | View all user solutions | Challenge discussion

    Array Min JumpsNot Completed

    Solutions: 161 | View all user solutions | Challenge discussion

    Nearest Smaller ValuesNot Completed

    Solutions: 314 | View all user solutions | Challenge discussion

    Matrix SpiralNot Completed

    Solutions: 129 | View all user solutions | Challenge discussion

    Word SplitNot Completed

    Solutions: 256 | View all user solutions | Challenge discussion

    Pair SearchingNot Completed

    Solutions: 80 | View all user solutions | Challenge discussion

    Boggle SolverNot Completed

    Solutions: 57 | View all user solutions | Challenge discussion

    HTML ElementsNot Completed

    Solutions: 94 | View all user solutions | Challenge discussion

    Missing Digit IINot Completed

    Solutions: 100 | View all user solutions | Challenge discussion

    Palindromic SubstringNot Completed

    Solutions: 161 | View all user solutions | Challenge discussion

    Trapping WaterNot Completed

    Solutions: 96 | View all user solutions | Challenge discussion

    Matrix PathNot Completed

    Solutions: 56 | View all user solutions | Challenge discussion

    Seating StudentsNot Completed

    Solutions: 86 | View all user solutions | Challenge discussion

    Longest Matrix PathNot Completed

    Solutions: 41 | View all user solutions | Challenge discussion

    Min Window SubstringNot Completed

    Solutions: 97 | View all user solutions | Challenge discussion

    Matrix ChainsNot Completed

    Solutions: 41 | View all user solutions | Challenge discussion

    Histogram AreaNot Completed

    Solutions: 64 | View all user solutions | Challenge discussion

    Matching CharactersNot Completed

    Solutions: 102 | View all user solutions | Challenge discussion

    Ternary ConverterNot Completed

    Solutions: 53 | View all user solutions | Challenge discussion

    Linear CongruenceNot Completed

    Solutions: 32 | View all user solutions | Challenge discussion

    Formatted NumberNot Completed

    Solutions: 113 | View all user solutions | Challenge discussion

    Largest Row ColumnNot Completed

    Solutions: 26 | View all user solutions | Challenge discussion

    Eight QueensNot Completed

    Solutions: 52 | View all user solutions | Challenge discussion

    Three PointsNot Completed

    Solutions: 72 | View all user solutions | Challenge discussion

    Character RemovalNot Completed

    Solutions: 82 | View all user solutions | Challenge discussion

    Simple PasswordNot Completed

    Solutions: 117 | View all user solutions | Challenge discussion

    Preorder TraversalNot Completed

    Solutions: 43 | View all user solutions | Challenge discussion

    String ZigzagNot Completed

    Solutions: 60 | View all user solutions | Challenge discussion

    Off BinaryNot Completed

    Solutions: 51 | View all user solutions | Challenge discussion

    Longest ConsecutiveNot Completed

    Solutions: 192 | View all user solutions | Challenge discussion

    String ExpressionNot Completed

    Solutions: 93 | View all user solutions | Challenge discussion

    Charlie the DogNot Completed

    Solutions: 26 | View all user solutions | Challenge discussion

    Plus MinusNot Completed

    Solutions: 43 | View all user solutions | Challenge discussion

    Hard Difficulty

    Shortest PathNot Completed

    Solutions: 1019 | View all user solutions | Challenge discussion

    Pattern ChaserNot Completed

    Solutions: 672 | View all user solutions | Challenge discussion

    CalculatorNot Completed

    Solutions: 1081 | View all user solutions | Challenge discussion

    Weighted PathNot Completed

    Solutions: 327 | View all user solutions | Challenge discussion

    Intersecting LinesNot Completed

    Solutions: 525 | View all user solutions | Challenge discussion

    RREF MatrixNot Completed

    Solutions: 113 | View all user solutions | Challenge discussion

    Polynomial ExpansionNot Completed

    Solutions: 270 | View all user solutions | Challenge discussion

    Gas StationNot Completed

    Solutions: 535 | View all user solutions | Challenge discussion

    Symmetric MatrixNot Completed

    Solutions: 371 | View all user solutions | Challenge discussion

    Switch SortNot Completed

    Solutions: 263 | View all user solutions | Challenge discussion

    Matrix DeterminantNot Completed

    Solutions: 245 | View all user solutions | Challenge discussion

    Queen CheckNot Completed

    Solutions: 423 | View all user solutions | Challenge discussion

    Noughts DeterminerNot Completed

    Solutions: 353 | View all user solutions | Challenge discussion

    Blackjack HighestNot Completed

    Solutions: 473 | View all user solutions | Challenge discussion

    Transitivity RelationsNot Completed

    Solutions: 399 | View all user solutions | Challenge discussion

    Alphabet Run EncryptionNot Completed

    Solutions: 228 | View all user solutions | Challenge discussion

    Knight JumpsNot Completed

    Solutions: 497 | View all user solutions | Challenge discussion

    Line OrderingNot Completed

    Solutions: 49 | View all user solutions | Challenge discussion

    Sudoku Quadrant CheckerNot Completed

    Solutions: 96 | View all user solutions | Challenge discussion

    Quick KnightNot Completed

    Solutions: 42 | View all user solutions | Challenge discussion

    Square FiguresNot Completed

    Solutions: 124 | View all user solutions | Challenge discussion

    Connect Four WinnerNot Completed

    Solutions: 66 | View all user solutions | Challenge discussion

    Array JumpingNot Completed

    Solutions: 51 | View all user solutions | Challenge discussion

    Matrix BorderNot Completed

    Solutions: 54 | View all user solutions | Challenge discussion

    Roman Numeral ReductionNot Completed

    Solutions: 64 | View all user solutions | Challenge discussion

    Parallel SumsNot Completed

    Solutions: 101 | View all user solutions | Challenge discussion

    LCSNot Completed

    Solutions: 59 | View all user solutions | Challenge discussion

    Nim WinnerNot Completed

    Solutions: 42 | View all user solutions | Challenge discussion

    Farthest NodesNot Completed

    Solutions: 137 | View all user solutions | Challenge discussion

    Optimal AssignmentsNot Completed

    Solutions: 478 | View all user solutions | Challenge discussion

    Kaprekars ConstantNot Completed

    Solutions: 92 | View all user solutions | Challenge discussion

    Hamiltonian PathNot Completed

    Solutions: 127 | View all user solutions | Challenge discussion

    Vertex CoveringNot Completed

    Solutions: 131 | View all user solutions | Challenge discussion

    Step WalkingNot Completed

    Solutions: 82 | View all user solutions | Challenge discussion

    Pascals TriangleNot Completed

    Solutions: 80 | View all user solutions | Challenge discussion

    Reverse Polish NotationNot Completed

    Solutions: 198 | View all user solutions | Challenge discussion

    Max Heap CheckerNot Completed

    Solutions: 83 | View all user solutions | Challenge discussion

    Chessboard TravelingNot Completed

    Solutions: 48 | View all user solutions | Challenge discussion

    Matching CouplesNot Completed

    Solutions: 95 | View all user solutions | Challenge discussion

    Approaching FibonacciNot Completed

    Solutions: 113 | View all user solutions | Challenge discussion

    Simple SATNot Completed

    Solutions: 61 | View all user solutions | Challenge discussion

    Array CouplesNot Completed

    Solutions: 90 | View all user solutions | Challenge discussion

    Array RotationNot Completed

    Solutions: 145 | View all user solutions | Challenge discussion

    Bracket CombinationsNot Completed

    Solutions: 97 | View all user solutions | Challenge discussion

    Counting AnagramsNot Completed

    Solutions: 125 | View all user solutions | Challenge discussion

    Maximal SquareNot Completed

    Solutions: 33 | View all user solutions | Challenge discussion

    Maximal RectangleNot Completed

    Solutions: 29 | View all user solutions | Challenge discussion

    Bipartite MatchingNot Completed

    Solutions: 25 | View all user solutions | Challenge discussion

    Pentagonal NumberNot Completed

    Solutions: 32 | View all user solutions | Challenge discussion

    City TrafficNot Completed

    Solutions: 24 | View all user solutions | Challenge discussion

    Convex Hull PointsNot Completed

    Solutions: 19 | View all user solutions | Challenge discussion

    Wildcard CharactersNot Completed

    Solutions: 34 | View all user solutions | Challenge discussion

    Companies

    • Google 33
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    All Tags

    • searching 98
    • array 68
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    • hash table 22
    • matrix 20
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    • algebra 9
    • game 9
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    • sorting 8
    • stack 7
    • sequences 7
    • chess 5
    • encoding 5
    • binary tree 5
    • linear algebra 4
    • geometry 4
    • character codes 3
    • set theory 3
    • prime numbers 3
    • heap 3
    • bitwise operation 2
    • cache 1