Brute Force Before Optimization

Context

In coding interviews at companies like Stripe, interviewers often care as much about problem-solving process as the final optimized answer. A brute-force solution is usually the fastest way to prove understanding and establish correctness before improving performance.

Core Question

Explain how you prioritize getting a working brute-force solution before optimizing. In your answer, address:

1. Why starting with a simple correct solution is valuable in an interview.
2. How you transition from brute force to a better algorithm.
3. What signals tell you that optimization is necessary, such as input size, repeated work, or avoidable nested loops.

Scope Guidance

The interviewer expects a structured explanation, not just “I start simple.” Discuss correctness first, complexity analysis, how to identify bottlenecks, and how you would communicate trade-offs while improving the solution.