Best Time to Buy and Sell Stock
Problem statement
Implement maxProfit for the classic Best Time to Buy and Sell Stock problem.
This Blind 75 version is framed for frontend interviews: write clean JavaScript, name the invariant out loud, and handle edge cases without over-engineering.
What this tests
- Pattern:
running minimum. - Ability to explain time and space complexity clearly.
- Careful handling of empty inputs, duplicates, and boundary cases.
- Production-style JavaScript readability, not just competitive-programming shortcuts.
Requirements & constraints
- Use JavaScript without external libraries.
- Prefer the standard optimal interview approach for this pattern.
- Return deterministic output when multiple valid outputs exist where the prompt implies ordering.
Examples
Example 1
Input: Use the canonical Blind 75 sample for this problem.
Output: Return the value required by the problem statement.
How to approach Best Time to Buy and Sell Stock
The strategy an interviewer expects you to reach for.
Senior Frontend Approach Start by identifying the pattern: running minimum. Then define the invariant the loop or recursion maintains before writing code.
The full solution is part of HelloFrontend Pro
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