Combinatorics Interview Questions for Quant Developers
Quant Developers get asked combinatorics differently from other quant roles - the emphasis shifts with what the job actually does. This is that slice.
85 questions, 77 of them free to practise right now. The split is 24 easy, 32 medium, 29 hard.
- A divisor of a power of tenEasyProbabilityCombinatoricsView →
- A majority of onesEasyCombinatoricsView →
- A repeated digit in the PINEasyProbabilityCombinatoricsView →
- An even palindromeEasyProbabilityCombinatoricsView →
- An odd subset with two small elementsEasyCombinatoricsView →
- Arranging colored balls in a lineEasyCombinatoricsView →
- BALLOON arrangements bookended by vowelsEasyCombinatoricsView →
- Codes with exactly one vowelEasyCombinatoricsView →
- Counting 8-bit stringsEasyCombinatoricsView →
- Counting nines to 1000EasyCombinatoricsBrainteasersView →
- Counting up-down walks to a targetEasyCombinatoricsView →
- Distinct-digit numbers using a 7EasyCombinatoricsView →
- Divisible by 2 or 3EasyCombinatoricsView →
- Divisible by neither 2 nor 3EasyCombinatoricsView →
- Handshakes across two groupsEasyCombinatoricsView →
- Hopping rabbitEasyProbabilityCombinatoricsView →
- Integers that contain a zeroEasyCombinatoricsBrainteasersView →
- Lattice paths through a checkpointEasyCombinatoricsView →
- MISSISSIPPI with the P's togetherEasyCombinatoricsView →
- Strictly increasing three-digit numbersEasyCombinatoricsView →
- Subsets containing one element but not anotherEasyCombinatoricsView →
- Three-one strings with matching endpointsEasyCombinatoricsView →
- Two ordering constraints at onceEasyProbabilityCombinatoricsView →
- Units digit of a random productEasyProbabilityCombinatoricsView →
- Anagrams of LOLLIPOPMediumCombinatoricsView →
- Balanced parenthesesMediumCombinatoricsProgramming & DSAView →
- Deleting every other number on a circleMediumCombinatoricsBrainteasersView →
- Distinct die labelingsMediumCombinatoricsBrainteasersView →
- Lattice paths in 3DMediumCombinatoricsView →
- Median of a list and its squaresMediumCombinatoricsStatisticsView →
- Monotone paths across a gridMediumCombinatoricsView →
- No two evens adjacentMediumCombinatoricsView →
- No two neighboring bulbs litMediumProbabilityCombinatoricsView →
- Non-attacking rooksMediumCombinatoricsView →
- Odd multiples of threeMediumCombinatoricsBrainteasersView →
- Odd solutions to a sumMediumCombinatoricsView →
- One random subset inside anotherMediumProbabilityCombinatoricsView →
- Placing operators among digitsMediumCombinatoricsView →
- Regions from ten linesMediumCombinatoricsBrainteasersView →
- Sum of multinomial coefficientsMediumCombinatoricsView →
- Sum of the pandigital numbersMediumCombinatoricsBrainteasersView →
- Summing digits to a millionMediumCombinatoricsBrainteasersView →
- Ten dice, sum divisible by sixMediumProbabilityCombinatoricsView →
- Terms in a multinomial expansionMediumCombinatoricsView →
- The die that makes sums uniformMediumProbabilityCombinatoricsView →
- Three-four-five in Pascal's triangleMediumCombinatoricsBrainteasersView →
- Tiling a stripMediumCombinatoricsView →
- Trailing zeros of 100!MediumCombinatoricsView →
- Units digit of a random powerMediumProbabilityCombinatoricsView →
- A rectangle over the shaded rowHardProbabilityCombinatoricsView →
- A weighted sum of binomialsHardCombinatoricsBrainteasersView →
- Average of near-diagonal numbersHardCombinatoricsBrainteasersView →
- Balls into bowls, three eachHardCombinatoricsView →
- 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 →
- Largest pairwise-coprime subset sumHardCombinatoricsBrainteasersView →
- Locks for a four-of-seven safeHardCombinatoricsBrainteasersView →
- 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 →
- 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 →
- Three eggs, nine dropsHardCombinatoricsBrainteasersView →
- Triangle with equal side sumsHardCombinatoricsBrainteasersView →
- When k-to-the-k is a squareHardCombinatoricsBrainteasersView →
- A family clustered at a round tableMediumCombinatorics Premium
- Climbing stairsMediumCombinatoricsProgramming & DSA Premium
- Last two digits of a powerMediumCombinatoricsBrainteasers Premium
- No two heads in a rowMediumProbabilityCombinatorics Premium
- Onto functionsMediumCombinatorics Premium
- Paths on a 4×3 gridMediumCombinatorics Premium
- Spaced onesMediumCombinatorics Premium
- Last one standingHardCombinatoricsBrainteasers Premium
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