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easy1 Head UpReviewedProbability · Akuna
easy7 Below IReviewedGames · Akuna
easy8-Sided DiceReviewedGames
easy9 AppearanceReviewedBrainteasers · Marshall Wace, Akuna
easyAcceptance-Rejection SamplingReviewedProbability
easyAlmost SquaresReviewedProbability
easyBaby BoyReviewedProbability · SIG, DE Shaw
easyBad BagelReviewedProbability · SIG, Jane Street
easyBasic Die Game VReviewedProbability · Jane Street
easyBelow DiagonalReviewedProbability
easyBertrand's BoxReviewedProbability · SIG, Goldman Sachs
easyBest So Far!ReviewedProbability
easyBeta DifferenceReviewedProbability
easyBinary StringsReviewedProbability
easyBlack or YellowReviewedBrainteasers
easyBlind DieReviewedProbability · Optiver, SIG
easyBowl of Cherries IVReviewedProbability
easyBoy-Girl LineReviewedProbability · SIG, Cubist
easyBreaking EvenReviewedProbability · Schonfeld, SIG
easyBridge CrossingReviewedBrainteasers · SIG, Jane Street
easyCaptive MarblesReviewedProbability · Flow Traders, Akuna
easyCar StopperReviewedProbability · Jane Street, SIG
easyCard TurnoverReviewedBrainteasers · Citadel
easyCarousel Box IReviewedProbability
easyCheesy Guy IReviewedProbability
easyChoosing a DieReviewedGames
easyCircly CoupleReviewedProbability · Virtu Financial, Citadel
easyCoin Swap IIReviewedProbability · SIG, Virtu Financial
easyColorful Run IReviewedProbability · Citadel
easyConfident Double HeadsReviewedProbability · DRW, SIG
easyConic CylinderReviewedProbability
easyCorner CatReviewedProbability · SIG
easyCorrelation Shift IReviewedProbability · Jane Street, Akuna
easyCounting GameReviewedBrainteasers · Optiver, SIG
easyCouple Pairs IReviewedProbability · SIG
easyCovariance Review IVReviewedProbability
easyCurrency CollectorReviewedProbability · SIG, DRW
easyDefective Cat PlushieReviewedProbability · Old Mission, SIG
easyDifferent Ball ColorsReviewedProbability · UBS, SIG
easyDisco Squares IReviewedProbability · Virtu Financial, Akuna
easyDistinct GlovesReviewedProbability · Jane Street, IMC
easyDot RemovalReviewedProbability · Jane Street
easyDouble Dice PayoffReviewedProbability · Jane Street
easyDuplicate Birth MonthReviewedBrainteasers · Jane Street, Belvedere Trading
easyDying PopulationReviewedProbability · IMC
easyEating PizzaReviewedProbability · SIG
easyEqual EndsReviewedProbability · SIG
easyEqual Flip TimerReviewedProbability · Flow Traders
easyEqual Unequal GameReviewedProbability · Squarepoint Capital
easyEven Card ConditionReviewedProbability
easyEvenly DoubleReviewedGames
easyExponential MaximaReviewedProbability
easyFresh BagelReviewedGames · WorldQuant, Valkyrie Trading
easyFull SolutionsReviewedPure Math · IMC, WorldQuant
easyGoat SearchReviewedProbability
easyGreater DiceReviewedProbability · Goldman Sachs, Chicago Trading Company
easyGroggy FroggyReviewedProbability · Citadel, Five Rings
easyHead-Tail ProductReviewedProbability
easyIncreasing ChainsReviewedProbability
easyInvestment ArbitrageReviewedFinance · SIG
easyJar MatchReviewedProbability · SIG
easyJellybean Jar IIReviewedProbability · Old Mission
easyKitten BoxReviewedProbability · Old Mission
easyLaser GameReviewedProbability
easyLight Bulb SwitchReviewedBrainteasers · Bank of America, Goldman Sachs
easyLight SwitchReviewedProbability · TransMarket Group
easyLimited Hitter IReviewedProbability · Jane Street
easyLonger Piece IReviewedProbability · Jane Street, SIG
easyLow Variance MeasureReviewedProbability
easyLucky LotteryReviewedProbability
easyMagic DoorsReviewedProbability
easyMagical Savanna IReviewedBrainteasers · Jane Street
easyMarathon RunnerReviewedBrainteasers · Jane Street, SIG
easyMarble Transfer IReviewedProbability · SIG
easyMaxima RangeReviewedProbability · WorldQuant, Citadel
easyMaximal DiceReviewedProbability · Akuna
easyMaximin UniformReviewedProbability · Citadel
easyMean PointReviewedProbability
easyMinimizer SquareReviewedProbability · Citadel
easyMinimum Variance PortfolioReviewedProbability
easyMissing Million IIReviewedProbability · Optiver
easyMoney ShorterReviewedProbability · Valkyrie Trading, Akuna
easyMultiballs IReviewedProbability · Jane Street
easyMulticoin IReviewedProbability
easyMultisocksReviewedProbability
easyMurder MysteryReviewedProbability
easyMystery DieReviewedBrainteasers · SIG
easyNiagara FallsReviewedBrainteasers · SIG
easyNo Ones HomeReviewedGames · SIG
easyOne Given IncreasingReviewedProbability · Optiver
easyOne Then TwoReviewedProbability · SIG
easyOpposite Parity Heads IReviewedProbability
easyPalindromey IIIReviewedProbability · Jane Street
easyPaperless Play IReviewedGames · Jane Street
easyParity DifferenceReviewedProbability
easyPerformance?ReviewedProbability · SIG
easyPoker PairReviewedProbability · SIG, Goldman Sachs
easyPrime SumReviewedProbability · Jane Street
easyProbability of Unfair Coin IReviewedProbability · Two Sigma, WorldQuant
easyProduct LimitReviewedProbability · Millennium Management
easyProportional CandlesReviewedBrainteasers
easyRainbow OrderingReviewedProbability
easyRandom ExamReviewedProbability
easyRandom Fixed PointReviewedProbability
easyRandom Rectangular AreaReviewedProbability
easyRemoved PortionReviewedProbability · Jane Street
easyRoom DividerReviewedProbability
easyRoyal Firsts IIReviewedProbability · Jane Street, Akuna
easyRunny Runs IReviewedProbability · Jane Street, SIG
easyRussian Roulette IIReviewedProbability · Jane Street, TransMarket Group
easySample Space ReductionReviewedProbability
easyScheduling AppointmentsReviewedProbability · Optiver, SIG
easyScholastic BooksReviewedProbability
easySelection InsideReviewedProbability
easyShip StopsReviewedProbability · IMC
easySimulation SchemeReviewedProbability · Optiver, Virtu Financial
easySniperReviewedProbability
easySoccer BetsReviewedProbability · SIG, Optiver
easySoccer ShopReviewedProbability
easyStart or Not IIReviewedGames · Citadel
easyStrictly Increasing DiceReviewedProbability · Jane Street
easySturdy Roof IIReviewedProbability
easySublime SnowmanReviewedProbability · SIG
easySum First IReviewedProbability · SIG
easySummed ProductsReviewedProbability
easySummy CovReviewedProbability
easyTallest to SmallestReviewedProbability
easyTeam SplitReviewedProbability · Old Mission, SIG
easyTen TenReviewedProbability
easyThe Biggest LoserReviewedProbability
easyThe Fixed One IReviewedProbability
easyThree Die SumReviewedProbability · Optiver, Old Mission
easyThree of a KindReviewedProbability · Jane Street, Goldman Sachs
easyThree RiflemenReviewedProbability · WorldQuant
easyTokyo Trains IReviewedProbability
easyToo Much Match IReviewedProbability
easyTriangular Angle IIReviewedProbability
easyTricky DieReviewedProbability
easyTrue EquationReviewedProbability
easyUnchanged Die PairReviewedProbability
easyUnder Oath IReviewedProbability · SIG, Virtu Financial
easyUniform FixReviewedProbability · Hudson River Trading, Citadel
easyVisible Number of HeadsReviewedProbability · DRW, Hudson River Trading
easyVolatile StockReviewedBrainteasers · SIG
easyWallet Bid IReviewedProbability
easyWild Card RoomReviewedProbability
easyYou Win?ReviewedProbability
easyZero AppearanceReviewedBrainteasers · Akuna
medium2 Below IReviewedProbability · Jane Street, Citadel
medium2 In A RowReviewedProbability
medium20-30 Die Split IIReviewedProbability · Jane Street, DRW
medium2D Paths IIIReviewedProbability
medium4Head IVReviewedProbability · Optiver, Jane Street
mediumAbsolute Normal DifferenceReviewedProbability · Citadel, DRW
mediumAdditive Dice IReviewedGames · Jane Street
mediumAll Values RepresentedReviewedProbability
mediumArithmetic Progression IIReviewedProbability
mediumBall OutReviewedProbability · SIG, Citadel
mediumBeer Barrel IIReviewedBrainteasers · Optiver
mediumBertrand's Paradox IReviewedProbability · Radix Trading
mediumBestie CardReviewedGames · Jane Street
mediumBetter in Red VReviewedProbability · SIG, Citadel
mediumBetween UniformsReviewedGames
mediumBig EnvelopeReviewedGames · SIG
mediumBinary OptionReviewedFinance
mediumBoy RatioReviewedProbability
mediumBrownian DifferenceReviewedPure Math
mediumBusted 6 IIReviewedProbability
mediumCar LineReviewedBrainteasers
mediumCard CompositionReviewedGames · Virtu Financial
mediumCard TurnerReviewedProbability · SIG
mediumCareful Side ChoiceReviewedProbability
mediumChess Tournament IIIReviewedProbability
mediumCircular Mismatch IReviewedProbability
mediumCoin OccurrencesReviewedGames · Jane Street
mediumCombinatorial ElectricianReviewedProbability · Jane Street
mediumConnected SquareReviewedProbability
mediumContainer Square IIReviewedProbability
mediumConvex QuadrilateralReviewedProbability
mediumCorner MeetReviewedProbability · Citadel
mediumCubic Ant IReviewedProbability · TransMarket Group, Jane Street
mediumCutting WoodReviewedProbability
mediumDeriving Put-Call Parity IIReviewedFinance
mediumDeterministic PokerReviewedGames
mediumDiagonal EigenvalueReviewedPure Math · Akuna, WorldQuant
mediumDistinct and GameyReviewedGames
mediumDollar Cent Switch IIReviewedBrainteasers
mediumDouble 5ReviewedProbability · SIG
mediumEgg Drop IReviewedBrainteasers · Aquatic Capital, TransMarket Group
mediumEven StevenReviewedProbability
mediumFamiliar NeighborsReviewedProbability
mediumFish SliceReviewedProbability · Citadel
mediumFlip AgainReviewedProbability · SIG
mediumFreedom DayReviewedBrainteasers · Five Rings
mediumGame Off IReviewedProbability
mediumGamma Coding IReviewedProbability
mediumGenerational Wealth IIReviewedProbability
mediumGenerous BankerReviewedProbability
mediumGraph Search IIReviewedProbability
mediumGreedy PiratesReviewedBrainteasers · SIG, Virtu Financial
mediumGrid IntersectionReviewedProbability · Optiver
mediumHasty HorsemanReviewedBrainteasers
mediumHigh-LowReviewedProbability
mediumHitting MGFReviewedPure Math
mediumIt's Black and WhiteReviewedProbability · DRW
mediumKeep or Play IReviewedGames
mediumKing ActivityReviewedProbability
mediumLarge MaximaReviewedProbability
mediumLast Color StandingReviewedProbability · Chicago Trading Company, Akuna
mediumLast CorrelationReviewedProbability
mediumLast Die LimitReviewedProbability · Jane Street
mediumLast Light Bulb StandingReviewedProbability
mediumLast Value TwoReviewedProbability
mediumLeap FrogReviewedProbability · DRW, Squarepoint Capital
mediumMake Your Martingale IIIReviewedPure Math
mediumMean DifferenceReviewedProbability
mediumMinimum MatchReviewedProbability · Five Rings
mediumMultiplicatively Decreasing IReviewedGames
mediumNon-Decreasing NumbersReviewedProbability
mediumOdd Coin FlipsReviewedProbability · Jane Street, Akuna
mediumOil TransportReviewedBrainteasers · Optiver, Akuna
mediumOptimal Ball DrawReviewedProbability · Jane Street, SIG
mediumOptimal Bidders IReviewedProbability · SIG
mediumOption Dice IIIReviewedFinance · Optiver, SIG
mediumOverflow IReviewedProbability
mediumParity StreaksReviewedProbability
mediumPartial Die EqualityReviewedProbability
mediumPartial Sums IReviewedProbability
mediumParticle Reach IIReviewedProbability
mediumPaying BailReviewedProbability · Old Mission
mediumPick Your Urn WiselyReviewedProbability · SIG, Jane Street
mediumPicky CasinoReviewedProbability
mediumPing Pong Tournament IIReviewedProbability · Five Rings, Two Sigma
mediumPoker Tourney IReviewedProbability · Arrowstreet Capital, Five Rings
mediumPower to the MatrixReviewedPure Math · Goldman Sachs
mediumPrecise N SumReviewedProbability
mediumPrime SubsetReviewedProbability
mediumProper ParenthesizationReviewedProbability · Citadel, Five Rings
mediumProportional Bets IReviewedProbability
mediumRadial MeasureReviewedProbability · WorldQuant
mediumRat Poison IIReviewedBrainteasers
mediumReciprocal SDEReviewedPure Math
mediumRewin IReviewedProbability · Jane Street
mediumRise and FallReviewedProbability · WorldQuant
mediumRuns!ReviewedProbability · Akuna
mediumSecretsReviewedProbability
mediumShip MeetingReviewedBrainteasers · WorldQuant
mediumSingle Double SumReviewedProbability
mediumSkater BoyReviewedProbability
mediumStone Pick IReviewedGames · Citadel
mediumStrange Coin IIReviewedProbability
mediumSum Over Min DieReviewedProbability
mediumTake and Roll IReviewedProbability · Jane Street
mediumTaxmanReviewedBrainteasers · IMC
mediumThank You, Quant!ReviewedProbability · Citadel, GSA Capital
mediumThe Perfect Hedge IIReviewedFinance
mediumThorough FrogReviewedProbability
mediumTic-Tac-Toe SumReviewedProbability · Optiver, Jane Street
mediumTranspositionsReviewedProbability
mediumTriangular SelectionReviewedProbability
mediumTricky Bob IReviewedProbability · Optiver
mediumTrue StatementReviewedBrainteasers · Jane Street
mediumTuple BirthdaysReviewedProbability
mediumUndirected Graph Search IReviewedProbability
mediumUniform Angle OverlapReviewedProbability
mediumUpdated First RoundReviewedProbability
mediumUpface CorrelationReviewedProbability · Squarepoint Capital
mediumVaried NumbersReviewedProbability
mediumVoid SuitsReviewedProbability
mediumWandering Ant IReviewedProbability