Explore questions associated with Citadel. Review the source details, then use the workspace for code, notes, and diagrams.
65 questions in the library. A source association does not guarantee a future interview question.
Behavioral and leadership · Coding · Machine learning · Other questions · System design
Loading questions…
Practice system design interviews out loud with an AI interviewer, a shared whiteboard and a scorecard for your level.
© 2026 SysRound. SysRound is an AI practice tool. The AI interviewer and the AI feedback can be wrong. Use it for your own practice, not to hire people.
Showing 26–50
Companies: Citadel
Design a Spreadsheet class with 26 columns and a specified number of rows that supports setCell and resetCell operations and stores integer values (unset cells…
Companies: Citadel, Discord
Array · Design · Hash Table · Matrix
Companies: Citadel
Model Evaluation · Regression & Statistical Modeling
Companies: Citadel
Regression & Statistical Modeling
Evaluate the integer value of an expression given in Reverse Polish Notation, where tokens are integers or the operators +, -, *, / and all…
Companies: Citadel, Google
Array · Math · Stack
Companies: Citadel
Gave you a sequence of operations that move a robot, ask if the sequence repeat infinite time, whether the robot will get back to original…
Companies: Citadel
Companies: Citadel
Companies: Citadel
Design a data structure supporting insert(val), remove(val), and getRandom() — which returns a uniformly random existing element — with each operation in average O(1) time…
Companies: Citadel, Amazon, Apple, Bloomberg +7
Array · Design · Hash Table · Math
Companies: Citadel
Companies: Citadel
Companies: Citadel
Companies: Citadel
Simulate batched buy/sell order matching where each buy matches with the lowest-price sell (and each sell with the highest-price buy), allowing partial fills until no…
Companies: Citadel, Amazon
Array · Heap (Priority Queue) · Simulation
Companies: Citadel
Companies: Citadel