Context

At companies like Stripe, interviewers often ask you to justify not only that a solution works, but also how efficient it is. Clear time complexity analysis shows that you understand the algorithm beyond the code.

Core Question

Explain the time complexity of your solution for a specific coding problem.

Address these points:

1. How do you determine time complexity from loops, recursion, and helper operations?
2. How do input size and data structure choices affect the final complexity?
3. How do you distinguish average, worst-case, and amortized complexity when relevant?

Scope Guidance

Give a practical interview-level explanation. You should be able to walk through a concrete solution, identify the dominant operations, simplify the expression using Big-O notation, and briefly mention space complexity if it materially affects the design.