Hard Quant Developer Interview Questions
Everything asked of quant developers, filtered to the hard end - useful for calibrating where you actually are.
53 questions, 44 of them free to practise right now. The topics that come up most are combinatorics (29), brainteasers (27), probability (11), calculus (6).
- A Fibonacci power sumHardBrainteasersView →
- A flea's shortest escape across a boxHardBrainteasersCalculusView →
- A function minus its derivativeHardCalculusView →
- A geometric series that sums to a squareHardBrainteasersView →
- A rectangle over the shaded rowHardProbabilityCombinatoricsView →
- A weighted sum of binomialsHardCombinatoricsBrainteasersView →
- Average of near-diagonal numbersHardCombinatoricsBrainteasersView →
- Balls into bowls, three eachHardCombinatoricsView →
- Cats and miceHardBrainteasersView →
- Cubes over the terminating denominatorsHardBrainteasersCalculusView →
- Dealing until kings or a king-and-aceHardCombinatoricsExpected ValueView →
- Digits with distinct pairwise sumsHardCombinatoricsBrainteasersView →
- Domino tilings of a 3×8 gridHardCombinatoricsView →
- Doors toggled by primesHardCombinatoricsBrainteasersView →
- Everyone gets one of eachHardProbabilityCombinatoricsView →
- How many long cycles?HardProbabilityCombinatoricsView →
- Laplace transform of a Brownian exit timeHardStochastic ProcessesView →
- Largest pairwise-coprime subset sumHardCombinatoricsBrainteasersView →
- Locks for a four-of-seven safeHardCombinatoricsBrainteasersView →
- Making a power of Brownian motion a martingaleHardStochastic ProcessesView →
- Mean of a mean-reverting processHardStochastic ProcessesFinance & DerivativesView →
- Measuring two pintsHardBrainteasersView →
- No two samples too closeHardProbabilityCombinatoricsView →
- Odd sums on a 3×3 gridHardProbabilityCombinatoricsView →
- Only seven left unchosenHardProbabilityCombinatoricsView →
- Pairing gloves within oneHardProbabilityCombinatoricsView →
- Pairing with a difference of 1 or 11HardCombinatoricsBrainteasersView →
- Rotations divisible by 37HardCombinatoricsBrainteasersView →
- Second moment of a Gaussian-kernel stochastic integralHardCalculusStochastic ProcessesView →
- Seven seated in age orderHardProbabilityCombinatoricsView →
- Shuffles to restore the deckHardCombinatoricsBrainteasersView →
- Smallest number with digit product 10000HardCombinatoricsBrainteasersView →
- Subsets with one consecutive pairHardCombinatoricsView →
- Sum of repeating decimalsHardCombinatoricsBrainteasersView →
- Sums of fours and fivesHardCombinatoricsBrainteasersView →
- Ten prime digits with a set productHardCombinatoricsView →
- The leap-frog's favorite landing spotHardProbabilityStochastic ProcessesView →
- The number with no new digitsHardBrainteasersView →
- The survivor in the circleHardBrainteasersView →
- Three eggs, nine dropsHardCombinatoricsBrainteasersView →
- Triangle with equal side sumsHardCombinatoricsBrainteasersView →
- Twelve balls, one oddHardBrainteasersView →
- When a power of the process is a submartingaleHardProbabilityStochastic ProcessesView →
- When k-to-the-k is a squareHardCombinatoricsBrainteasersView →
- Absorption in naive floating-point summationHardCalculusProgramming & DSA Premium
- Expected comparisons, from first principlesHardProgramming & DSA Premium
- Last one standingHardCombinatoricsBrainteasers Premium
- Median of a streamHardStatisticsProgramming & DSA Premium
- Minimum coins where greedy failsHardProgramming & DSA Premium
- Prisoners and the boxesHardProbabilityBrainteasers Premium
- Reservoir samplingHardStatisticsProgramming & DSA Premium
- Two Newton iterations for a square rootHardCalculusProgramming & DSA Premium
- Two eggs, 100 floorsHardBrainteasers Premium
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