Problems
Each problem is a small multi-file project with seeded bugs (or a missing feature), visible tests and hidden tests. Pick one, fix it, and submit. Problems marked Sign in need a free account.
- 05
05Pickup Locker Network
Pickup locker network (implement assign)
C++MediumFeature60 min - 10
10Cart Promotion Pricing Engine
Cart promotion pricing engine (implement price)
Java · Spring BootMediumFeature60 minSign in - 14
14Loyalty Points Calculator
Loyalty points calculator (implement pointsForOrder; tiers, redemptions)
C++EasyFeature60 min - 17
17Driver Shift Planner
Driver shift planner (implement chooseDriver; rest rule, daily max)
C++MediumFeature60 minSign in - 20
20Subscription Renewal Billing
Subscription renewal billing (implement prorationCharge; anchors, retries, transitions)
C++HardFeature60 minSign in - 24
24Review Helpfulness Votes API
Review helpfulness votes REST API (implement rank; votes, burying, tie-breaks)
Java · Spring BootEasyFeature60 min - 27
27Loyalty Points Ledger API
Loyalty points ledger REST API (implement plan; expiring lots, FIFO redemptions, retries)
Java · Spring BootMediumFeature60 minSign in - 30
30Refund Processing API
Refund processing REST API (implement split; idempotency order, money parsing, window, reasons)
Java · Spring BootHardFeature60 minSign in