Determine the Winner of a Bowling Game
A easy-tier problem at 36% community acceptance, tagged with Array, Simulation. Reported in interviews at DE Shaw and 0 others.
Bowling scoring breaks most people because it's not just adding pins. A spare (knocking down all pins in two rolls) or strike (all pins in one roll) means bonus points from future rolls, and you have to simulate the whole game frame by frame to get it right. Determine the Winner of a Bowling Game appears in assessments from DE Shaw and other finance-heavy shops where you need to write clean simulation logic without off-by-one errors. If you blank on the bonus structure during your live OA, StealthCoder surfaces a working solution in seconds, invisible to the proctor.
Companies that ask "Determine the Winner of a Bowling Game"
Determine the Winner of a Bowling Game is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Built by an Amazon engineer who used it to pass JPMorgan's OA and system design loop.
Get StealthCoderThe trap is treating bowling like simple addition. You can't just add up pins per frame because strikes and spares grant bonus points from the next one or two rolls. You need to iterate through frames, track which rolls are part of which frame (frames 1-9 are normal, frame 10 is special and can have up to three rolls), and apply bonus multipliers correctly. Most candidates write frame logic, then break on bonus calculation or frame 10 edge cases. The obvious approach of just summing scores falls apart immediately. Simulation is the only reliable path: loop through rolls, maintain frame state, detect strikes and spares, add bonuses as you confirm future rolls, and handle the 10th frame separately since it can contain up to three rolls. StealthCoder is the hedge if the bonus logic or frame 10 rules trip you up.
Pattern tags
You know the problem.
Make sure you actually pass it.
Determine the Winner of a Bowling Game recycles across companies for a reason. It's easy-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Built by an Amazon engineer who used it to pass JPMorgan's OA and system design loop. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Determine the Winner of a Bowling Game interview FAQ
Why is this bowling problem hard if it's marked EASY?+
The acceptance rate is about 36 percent, well below typical EASY difficulty, because the bonus system trips up candidates who don't simulate frame-by-frame. Strikes and spares require reading ahead into future rolls, and the 10th frame breaks the normal structure. Once you nail the simulation loop and bonus logic, it's straightforward.
Do I need to know real bowling rules to solve this?+
Yes. The problem defines the rules, but you need to understand strikes (all pins, one roll, adds next two rolls as bonus), spares (all pins, two rolls, adds next one roll), and that the 10th frame is different (can have three rolls if you get a strike or spare). Simulate exactly as the problem specifies.
What's the most common mistake on this problem?+
Not handling the 10th frame separately or applying bonuses before you've confirmed all future rolls exist. Also, off-by-one errors when indexing into the rolls array while jumping over strike rolls that only use one roll per frame. Trace through a strike scenario step by step.
Is this problem still asked at companies like DE Shaw?+
Yes, it appears in their assessments. Firms that value clean simulation and careful state management ask this. It's not about algorithmic wizardry, it's about writing correct, readable code under pressure.
What topics should I review before hitting this in an OA?+
Array indexing and iteration are core, but this is really a Simulation problem. Focus on maintaining state (current frame, current roll index) and applying conditional logic (is this a strike, spare, or open frame?). Practice parsing the problem's rules into code.
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