OOPS pillars & SOLID principles + DSA Heap

Interview questions to prep

1. Why is a heap the right structure? Could a balanced BST or sorted list work — why is heap better?
2. Explain the heap-of-k pattern: keep size k, push new, pop if over k. What's the resulting complexity?
3. What does the comparator look like, and how would you tweak it to flip min/max behaviour?

Interview questions to prep

1. Compare heap (O(n log k)), sort (O(n log n)), quickselect (O(n) avg) — when does each fit?
2. What's quickselect's worst case, and how do you avoid it (median-of-medians, randomization)?

Interview questions to prep

1. Walk through the four pillars of OOP with code examples.
2. When does composition beat inheritance?

Interview questions to prep

1. Walk through each SOLID principle with a real example.
2. Which SOLID principle do you violate most often, and why?

Interview questions to prep

1. Spot a god class — what would you refactor it into?
2. Why are deep inheritance hierarchies usually a smell, and what do you reach for instead?