Understand — read the problem, inputs, output, and examples. Say in your own words what must be returned.
Choose the tools — identify the useful data structure or pattern: list, string, set, dictionary, stack, queue, two pointers, etc. If the concept or Python operation is unclear, use Learn basics.
Plan — work through one small example and write the steps before coding. If you understand the concept but are stuck applying it, use Hint.
Code — implement the plan clearly. Start with the simplest correct approach you understand.
Analyze — identify Time O(...) and Space O(...). Ask whether another correct approach is simpler or more efficient.
Run — test it. If it fails, use the failing case to trace what your code actually did.
Review — after passing, compare with the sample answer, complexity, and alternative solution.
Coding concept map
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