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    WildcardsNot Completed

    Solutions: 11 | View user solutions | Added 09/12/18

    String CalculateNot Completed

    Solutions: 18 | View user solutions | Added 09/10/18

    PrimesNot Completed

    Solutions: 45 | View user solutions | Added 08/29/18

    Free Challenges

    Longest WordNot Completed

    Solutions: 76175 | Step-by-step solution | Challenge discussion

    First FactorialNot Completed

    Solutions: 95398 | Step-by-step solution | Challenge discussion

    First ReverseNot Completed

    Solutions: 117050 | Step-by-step solution | Challenge discussion

    Letter ChangesNot Completed

    Solutions: 72369 | Step-by-step solution | Challenge discussion

    Simple AddingNot Completed

    Solutions: 59024 | Step-by-step solution | Challenge discussion

    Letter CapitalizeNot Completed

    Solutions: 50203 | Step-by-step solution | Challenge discussion

    Simple SymbolsNot Completed

    Solutions: 42718 | Step-by-step solution | Challenge discussion

    Check NumsNot Completed

    Solutions: 43217 | Step-by-step solution | Challenge discussion

    Time ConvertNot Completed

    Solutions: 32897 | Step-by-step solution | Challenge discussion

    Alphabet SoupNot Completed

    Solutions: 30260 | Step-by-step solution | Challenge discussion

    Kaprekars ConstantNot Completed

    Solutions: 4838 | View all user solutions | Challenge discussion

    Chessboard TravelingNot Completed

    Solutions: 2075 | View all user solutions | Challenge discussion

    Maximal SquareNot Completed

    Solutions: 1335 | View all user solutions | Challenge discussion

    Pentagonal NumberNot Completed

    Solutions: 1422 | View all user solutions | Challenge discussion

    Correct PathNot Completed

    Solutions: 1611 | View all user solutions | Challenge discussion

    Scale BalancingNot Completed

    Solutions: 2209 | View all user solutions | Challenge discussion

    Vowel SquareNot Completed

    Solutions: 1414 | View all user solutions | Challenge discussion

    Eight QueensNot Completed

    Solutions: 1107 | View all user solutions | Challenge discussion

    Closest Enemy IINot Completed

    Solutions: 1246 | View all user solutions | Challenge discussion

    Questions MarksNot Completed

    Solutions: 3659 | View all user solutions | Challenge discussion

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    Easy Difficulty

    First ReverseNot Completed

    Solutions: 117050 | Step-by-step solution | Challenge discussion

    First FactorialNot Completed

    Solutions: 95398 | Step-by-step solution | Challenge discussion

    Longest WordNot Completed

    Solutions: 76175 | Step-by-step solution | Challenge discussion

    Letter ChangesNot Completed

    Solutions: 72369 | Step-by-step solution | Challenge discussion

    Simple AddingNot Completed

    Solutions: 59024 | Step-by-step solution | Challenge discussion

    Letter CapitalizeNot Completed

    Solutions: 50203 | Step-by-step solution | Challenge discussion

    Simple SymbolsNot Completed

    Solutions: 42718 | Step-by-step solution | Challenge discussion

    Check NumsNot Completed

    Solutions: 43217 | Step-by-step solution | Challenge discussion

    Time ConvertNot Completed

    Solutions: 32897 | Step-by-step solution | Challenge discussion

    Alphabet SoupNot Completed

    Solutions: 30260 | Step-by-step solution | Challenge discussion

    AB CheckNot Completed

    Solutions: 17006 | Step-by-step solution | Challenge discussion

    Vowel CountNot Completed

    Solutions: 15630 | Step-by-step solution | Challenge discussion

    Word CountNot Completed

    Solutions: 14763 | Step-by-step solution | Challenge discussion

    Ex OhNot Completed

    Solutions: 14460 | Step-by-step solution | Challenge discussion

    PalindromeNot Completed

    Solutions: 16856 | Step-by-step solution | Challenge discussion

    Arith GeoNot Completed

    Solutions: 13426 | Step-by-step solution | Challenge discussion

    Array Addition INot Completed

    Solutions: 8628 | Step-by-step solution | Challenge discussion

    Letter Count INot Completed

    Solutions: 7901 | Step-by-step solution | Challenge discussion

    Second GreatLowNot Completed

    Solutions: 13099 | Step-by-step solution | Challenge discussion

    Division StringifiedNot Completed

    Solutions: 9817 | Step-by-step solution | Challenge discussion

    Counting Minutes INot Completed

    Solutions: 5822 | Step-by-step solution | Challenge discussion

    Mean ModeNot Completed

    Solutions: 7609 | Step-by-step solution | Challenge discussion

    Dash InsertNot Completed

    Solutions: 8629 | Step-by-step solution | Challenge discussion

    Swap CaseNot Completed

    Solutions: 8166 | Step-by-step solution | Challenge discussion

    Number AdditionNot Completed

    Solutions: 8040 | Step-by-step solution | Challenge discussion

    Third GreatestNot Completed

    Solutions: 7448 | Step-by-step solution | Challenge discussion

    Powers of TwoNot Completed

    Solutions: 8321 | Step-by-step solution | Challenge discussion

    Additive PersistenceNot Completed

    Solutions: 5935 | Step-by-step solution | Challenge discussion

    Multiplicative PersistenceNot Completed

    Solutions: 4572 | Step-by-step solution | Challenge discussion

    Off Line MinimumNot Completed

    Solutions: 6162 | Step-by-step solution | Challenge discussion

    Changing SequenceNot Completed

    Solutions: 2552 | Step-by-step solution | Challenge discussion

    Overlapping RangesNot Completed

    Solutions: 2564 | Step-by-step solution | Challenge discussion

    SuperincreasingNot Completed

    Solutions: 2611 | Step-by-step solution | Challenge discussion

    Hamming DistanceNot Completed

    Solutions: 1788 | Step-by-step solution | Challenge discussion

    Rectangle AreaNot Completed

    Solutions: 2166 | Step-by-step solution | Challenge discussion

    Bitwise OneNot Completed

    Solutions: 1760 | Step-by-step solution | Challenge discussion

    Other ProductsNot Completed

    Solutions: 1806 | Step-by-step solution | Challenge discussion

    Wave SortingNot Completed

    Solutions: 1253 | Step-by-step solution | Challenge discussion

    Array MatchingNot Completed

    Solutions: 1560 | Step-by-step solution | Challenge discussion

    Binary ReversalNot Completed

    Solutions: 1275 | Step-by-step solution | Challenge discussion

    Longest Increasing SequenceNot Completed

    Solutions: 1226 | Step-by-step solution | Challenge discussion

    Even PairsNot Completed

    Solutions: 1178 | Step-by-step solution | Challenge discussion

    Next PalindromeNot Completed

    Solutions: 1021 | Step-by-step solution | Challenge discussion

    Largest PairNot Completed

    Solutions: 1364 | Step-by-step solution | Challenge discussion

    Nonrepeating CharacterNot Completed

    Solutions: 1027 | Step-by-step solution | Challenge discussion

    Two SumNot Completed

    Solutions: 1856 | Step-by-step solution | Challenge discussion

    Bitwise TwoNot Completed

    Solutions: 731 | Step-by-step solution | Challenge discussion

    Power Set CountNot Completed

    Solutions: 1065 | Step-by-step solution | Challenge discussion

    Product DigitsNot Completed

    Solutions: 1340 | Step-by-step solution | Challenge discussion

    Palindrome CreatorNot Completed

    Solutions: 1108 | Step-by-step solution | Challenge discussion

    Basic Roman NumeralsNot Completed

    Solutions: 741 | Step-by-step solution | Challenge discussion

    Food DistributionNot Completed

    Solutions: 629 | Step-by-step solution | Challenge discussion

    Three SumNot Completed

    Solutions: 755 | Step-by-step solution | Challenge discussion

    Correct PathNot Completed

    Solutions: 1611 | Step-by-step solution | Challenge discussion

    Scale BalancingNot Completed

    Solutions: 2209 | Step-by-step solution | Challenge discussion

    Three NumbersNot Completed

    Solutions: 713 | Step-by-step solution | Challenge discussion

    Alphabet SearchingNot Completed

    Solutions: 612 | Step-by-step solution | Challenge discussion

    Time DifferenceNot Completed

    Solutions: 396 | Step-by-step solution | Challenge discussion

    Triangle RowNot Completed

    Solutions: 379 | Step-by-step solution | Challenge discussion

    Vowel SquareNot Completed

    Solutions: 1414 | Step-by-step solution | Challenge discussion

    Closest EnemyNot Completed

    Solutions: 578 | Step-by-step solution | Challenge discussion

    Closest Enemy IINot Completed

    Solutions: 1246 | Step-by-step solution | Challenge discussion

    Number StreamNot Completed

    Solutions: 388 | Step-by-step solution | Challenge discussion

    Largest FourNot Completed

    Solutions: 570 | Step-by-step solution | Challenge discussion

    Distinct CharactersNot Completed

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

    Questions MarksNot Completed

    Solutions: 3659 | Step-by-step solution | Challenge discussion

    Camel CaseNot Completed

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

    ASCII ConversionNot Completed

    Solutions: 335 | Step-by-step solution | Challenge discussion

    Simple EvensNot Completed

    Solutions: 458 | Step-by-step solution | Challenge discussion

    Snake CaseNot Completed

    Solutions: 401 | Step-by-step solution | Challenge discussion

    Sum MultiplierNot Completed

    Solutions: 498 | Step-by-step solution | Challenge discussion

    String MergeNot Completed

    Solutions: 470 | Step-by-step solution | Challenge discussion

    One DecrementedNot Completed

    Solutions: 441 | Step-by-step solution | Challenge discussion

    Element MergerNot Completed

    Solutions: 469 | Step-by-step solution | Challenge discussion

    GCFNot Completed

    Solutions: 440 | Step-by-step solution | Challenge discussion

    Serial NumberNot Completed

    Solutions: 595 | Step-by-step solution | Challenge discussion

    String PeriodsNot Completed

    Solutions: 505 | Step-by-step solution | Challenge discussion

    Palindrome SwapperNot Completed

    Solutions: 316 | Step-by-step solution | Challenge discussion

    Remove BracketsNot Completed

    Solutions: 456 | Step-by-step solution | Challenge discussion

    Command LineNot Completed

    Solutions: 205 | Step-by-step solution | Challenge discussion

    Star RatingNot Completed

    Solutions: 418 | Step-by-step solution | Challenge discussion

    Moving MedianNot Completed

    Solutions: 175 | Step-by-step solution | Challenge discussion

    Group TotalsNot Completed

    Solutions: 166 | Step-by-step solution | Challenge discussion

    String ChangesNot Completed

    Solutions: 43 | Step-by-step solution | Challenge discussion

    FizzBuzzNot Completed

    Solutions: 70 | Step-by-step solution | Challenge discussion

    H DistanceNot Completed

    Solutions: 29 | Step-by-step solution | Challenge discussion

    Different CasesNot Completed

    Solutions: 40 | Step-by-step solution | Challenge discussion

    Medium Difficulty

    Prime TimeNot Completed

    Solutions: 12080 | Step-by-step solution | Challenge discussion

    Run Length Not Completed

    Solutions: 8608 | Step-by-step solution | Challenge discussion

    Prime MoverNot Completed

    Solutions: 7457 | Step-by-step solution | Challenge discussion

    Palindrome TwoNot Completed

    Solutions: 7141 | Step-by-step solution | Challenge discussion

    DivisionNot Completed

    Solutions: 6648 | Step-by-step solution | Challenge discussion

    String ScrambleNot Completed

    Solutions: 7298 | Step-by-step solution | Challenge discussion

    Arith Geo IINot Completed

    Solutions: 4999 | Step-by-step solution | Challenge discussion

    Array AdditionNot Completed

    Solutions: 4413 | Step-by-step solution | Challenge discussion

    Binary ConverterNot Completed

    Solutions: 4527 | Step-by-step solution | Challenge discussion

    Letter CountNot Completed

    Solutions: 4489 | Step-by-step solution | Challenge discussion

    Caesar CipherNot Completed

    Solutions: 5150 | Step-by-step solution | Challenge discussion

    Simple ModeNot Completed

    Solutions: 5013 | Step-by-step solution | Challenge discussion

    ConsecutiveNot Completed

    Solutions: 4115 | Step-by-step solution | Challenge discussion

    Formatted DivisionNot Completed

    Solutions: 3792 | Step-by-step solution | Challenge discussion

    Counting MinutesNot Completed

    Solutions: 2793 | View all user solutions | Challenge discussion

    Permutation StepNot Completed

    Solutions: 3322 | View all user solutions | Challenge discussion

    Prime CheckerNot Completed

    Solutions: 2552 | View all user solutions | Challenge discussion

    Dash Insert IINot Completed

    Solutions: 4934 | View all user solutions | Challenge discussion

    Swap IINot Completed

    Solutions: 2744 | View all user solutions | Challenge discussion

    Number SearchNot Completed

    Solutions: 3360 | View all user solutions | Challenge discussion

    Triple DoubleNot Completed

    Solutions: 3126 | View all user solutions | Challenge discussion

    Bracket MatcherNot Completed

    Solutions: 2845 | View all user solutions | Challenge discussion

    String ReductionNot Completed

    Solutions: 2354 | View all user solutions | Challenge discussion

    ThreeFive MultiplesNot Completed

    Solutions: 2839 | View all user solutions | Challenge discussion

    Binary Search Tree LCANot Completed

    Solutions: 287 | View all user solutions | Challenge discussion

    Coin DeterminerNot Completed

    Solutions: 2308 | View all user solutions | Challenge discussion

    Fibonacci CheckerNot Completed

    Solutions: 2652 | View all user solutions | Challenge discussion

    Multiple BracketsNot Completed

    Solutions: 2357 | View all user solutions | Challenge discussion

    Most Free TimeNot Completed

    Solutions: 1417 | View all user solutions | Challenge discussion

    Overlapping RectanglesNot Completed

    Solutions: 1618 | View all user solutions | Challenge discussion

    Look Say SequenceNot Completed

    Solutions: 1474 | View all user solutions | Challenge discussion

    Distinct ListNot Completed

    Solutions: 2402 | View all user solutions | Challenge discussion

    Number EncodingNot Completed

    Solutions: 1494 | View all user solutions | Challenge discussion

    Stock PickerNot Completed

    Solutions: 742 | View all user solutions | Challenge discussion

    Max SubarrayNot Completed

    Solutions: 660 | View all user solutions | Challenge discussion

    Missing DigitNot Completed

    Solutions: 450 | View all user solutions | Challenge discussion

    K Unique CharactersNot Completed

    Solutions: 450 | View all user solutions | Challenge discussion

    Bitmap HolesNot Completed

    Solutions: 328 | View all user solutions | Challenge discussion

    Symmetric TreeNot Completed

    Solutions: 290 | View all user solutions | Challenge discussion

    Binary Tree LCANot Completed

    Solutions: 158 | View all user solutions | Challenge discussion

    LRU CacheNot Completed

    Solutions: 191 | View all user solutions | Challenge discussion

    Tree ConstructorNot Completed

    Solutions: 298 | View all user solutions | Challenge discussion

    Array Min JumpsNot Completed

    Solutions: 232 | View all user solutions | Challenge discussion

    Nearest Smaller ValuesNot Completed

    Solutions: 409 | View all user solutions | Challenge discussion

    Matrix SpiralNot Completed

    Solutions: 199 | View all user solutions | Challenge discussion

    Word SplitNot Completed

    Solutions: 372 | View all user solutions | Challenge discussion

    Pair SearchingNot Completed

    Solutions: 125 | View all user solutions | Challenge discussion

    Boggle SolverNot Completed

    Solutions: 95 | View all user solutions | Challenge discussion

    HTML ElementsNot Completed

    Solutions: 160 | View all user solutions | Challenge discussion

    Missing Digit IINot Completed

    Solutions: 156 | View all user solutions | Challenge discussion

    Palindromic SubstringNot Completed

    Solutions: 262 | View all user solutions | Challenge discussion

    Trapping WaterNot Completed

    Solutions: 157 | View all user solutions | Challenge discussion

    Matrix PathNot Completed

    Solutions: 82 | View all user solutions | Challenge discussion

    Seating StudentsNot Completed

    Solutions: 155 | View all user solutions | Challenge discussion

    Longest Matrix PathNot Completed

    Solutions: 74 | View all user solutions | Challenge discussion

    Min Window SubstringNot Completed

    Solutions: 157 | View all user solutions | Challenge discussion

    Matrix ChainsNot Completed

    Solutions: 70 | View all user solutions | Challenge discussion

    Histogram AreaNot Completed

    Solutions: 121 | View all user solutions | Challenge discussion

    Matching CharactersNot Completed

    Solutions: 177 | View all user solutions | Challenge discussion

    Ternary ConverterNot Completed

    Solutions: 95 | View all user solutions | Challenge discussion

    Linear CongruenceNot Completed

    Solutions: 58 | View all user solutions | Challenge discussion

    Formatted NumberNot Completed

    Solutions: 197 | View all user solutions | Challenge discussion

    Largest Row ColumnNot Completed

    Solutions: 57 | View all user solutions | Challenge discussion

    Eight QueensNot Completed

    Solutions: 1107 | View all user solutions | Challenge discussion

    Three PointsNot Completed

    Solutions: 134 | View all user solutions | Challenge discussion

    Character RemovalNot Completed

    Solutions: 148 | View all user solutions | Challenge discussion

    Simple PasswordNot Completed

    Solutions: 198 | View all user solutions | Challenge discussion

    Preorder TraversalNot Completed

    Solutions: 92 | View all user solutions | Challenge discussion

    String ZigzagNot Completed

    Solutions: 100 | View all user solutions | Challenge discussion

    Off BinaryNot Completed

    Solutions: 85 | View all user solutions | Challenge discussion

    Longest ConsecutiveNot Completed

    Solutions: 304 | View all user solutions | Challenge discussion

    String ExpressionNot Completed

    Solutions: 142 | View all user solutions | Challenge discussion

    Charlie the DogNot Completed

    Solutions: 74 | View all user solutions | Challenge discussion

    Plus MinusNot Completed

    Solutions: 120 | View all user solutions | Challenge discussion

    PrimesNot Completed

    Solutions: 45 | View all user solutions | Challenge discussion

    String CalculateNot Completed

    Solutions: 18 | View all user solutions | Challenge discussion

    Hard Difficulty

    Sudoku Quadrant CheckerNot Completed

    Solutions: 127 | View all user solutions | Challenge discussion

    Optimal AssignmentsNot Completed

    Solutions: 522 | View all user solutions | Challenge discussion

    Transitivity RelationsNot Completed

    Solutions: 417 | View all user solutions | Challenge discussion

    Shortest PathNot Completed

    Solutions: 1176 | View all user solutions | Challenge discussion

    Polynomial ExpansionNot Completed

    Solutions: 298 | View all user solutions | Challenge discussion

    CalculatorNot Completed

    Solutions: 1169 | View all user solutions | Challenge discussion

    Pattern ChaserNot Completed

    Solutions: 761 | View all user solutions | Challenge discussion

    Weighted PathNot Completed

    Solutions: 366 | View all user solutions | Challenge discussion

    RREF MatrixNot Completed

    Solutions: 134 | View all user solutions | Challenge discussion

    Intersecting LinesNot Completed

    Solutions: 576 | View all user solutions | Challenge discussion

    Kaprekars ConstantNot Completed

    Solutions: 4838 | View all user solutions | Challenge discussion

    Hamiltonian PathNot Completed

    Solutions: 149 | View all user solutions | Challenge discussion

    Step WalkingNot Completed

    Solutions: 114 | View all user solutions | Challenge discussion

    Gas StationNot Completed

    Solutions: 586 | View all user solutions | Challenge discussion

    Symmetric MatrixNot Completed

    Solutions: 410 | View all user solutions | Challenge discussion

    Switch SortNot Completed

    Solutions: 288 | View all user solutions | Challenge discussion

    Matrix DeterminantNot Completed

    Solutions: 272 | View all user solutions | Challenge discussion

    Queen CheckNot Completed

    Solutions: 472 | View all user solutions | Challenge discussion

    Noughts DeterminerNot Completed

    Solutions: 383 | View all user solutions | Challenge discussion

    Blackjack HighestNot Completed

    Solutions: 530 | View all user solutions | Challenge discussion

    Alphabet Run EncryptionNot Completed

    Solutions: 249 | View all user solutions | Challenge discussion

    Vertex CoveringNot Completed

    Solutions: 145 | View all user solutions | Challenge discussion

    Knight JumpsNot Completed

    Solutions: 526 | View all user solutions | Challenge discussion

    Farthest NodesNot Completed

    Solutions: 156 | View all user solutions | Challenge discussion

    Line OrderingNot Completed

    Solutions: 72 | View all user solutions | Challenge discussion

    Quick KnightNot Completed

    Solutions: 64 | View all user solutions | Challenge discussion

    Square FiguresNot Completed

    Solutions: 152 | View all user solutions | Challenge discussion

    Connect Four WinnerNot Completed

    Solutions: 110 | View all user solutions | Challenge discussion

    Array JumpingNot Completed

    Solutions: 84 | View all user solutions | Challenge discussion

    Matrix BorderNot Completed

    Solutions: 81 | View all user solutions | Challenge discussion

    Roman Numeral ReductionNot Completed

    Solutions: 98 | View all user solutions | Challenge discussion

    Parallel SumsNot Completed

    Solutions: 155 | View all user solutions | Challenge discussion

    LCSNot Completed

    Solutions: 96 | View all user solutions | Challenge discussion

    Nim WinnerNot Completed

    Solutions: 58 | View all user solutions | Challenge discussion

    Pascals TriangleNot Completed

    Solutions: 116 | View all user solutions | Challenge discussion

    Reverse Polish NotationNot Completed

    Solutions: 222 | View all user solutions | Challenge discussion

    Max Heap CheckerNot Completed

    Solutions: 106 | View all user solutions | Challenge discussion

    Chessboard TravelingNot Completed

    Solutions: 2075 | View all user solutions | Challenge discussion

    Matching CouplesNot Completed

    Solutions: 125 | View all user solutions | Challenge discussion

    Approaching FibonacciNot Completed

    Solutions: 147 | View all user solutions | Challenge discussion

    Simple SATNot Completed

    Solutions: 80 | View all user solutions | Challenge discussion

    Array CouplesNot Completed

    Solutions: 116 | View all user solutions | Challenge discussion

    Bracket CombinationsNot Completed

    Solutions: 139 | View all user solutions | Challenge discussion

    Counting AnagramsNot Completed

    Solutions: 173 | View all user solutions | Challenge discussion

    Array RotationNot Completed

    Solutions: 180 | View all user solutions | Challenge discussion

    Maximal SquareNot Completed

    Solutions: 1335 | View all user solutions | Challenge discussion

    Maximal RectangleNot Completed

    Solutions: 47 | View all user solutions | Challenge discussion

    Bipartite MatchingNot Completed

    Solutions: 48 | View all user solutions | Challenge discussion

    Pentagonal NumberNot Completed

    Solutions: 1422 | View all user solutions | Challenge discussion

    City TrafficNot Completed

    Solutions: 49 | View all user solutions | Challenge discussion

    Convex Hull PointsNot Completed

    Solutions: 32 | View all user solutions | Challenge discussion

    Wildcard CharactersNot Completed

    Solutions: 82 | View all user solutions | Challenge discussion

    Tetris MoveNot Completed

    Solutions: 35 | View all user solutions | Challenge discussion

    WildcardsNot Completed

    Solutions: 11 | View all user solutions | Challenge discussion

    Difficulty

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