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Max-Heapify Operations and Comparisons (Variation 10)

Asked by NileshNama | Textbook Reference: CLRS Algorithms


Consider a max-heap stored in an array: `[10, 8, 7, 5, 4, 6, 2]`. We want to insert a new element `9` into this max-heap. What is the state of the array representation of the heap after the insertion is complete?

Community Explanations (3)

[Variation 10 Explanation] Let's insert 9: 1. Insert at end: `[10, 8, 7, 5, 4, 6, 2, 9]` 2. Swap 9 with parent 5: `[10, 8, 7, 9, 4, 6, 2, 5]` 3. Swap 9 with parent 8: `[10, 9, 7, 8, 4, 6, 2, 5]` 4. Compare 9 with parent 10 ($9 < 10$), stop. Final array: `[10, 9, 7, 8, 4, 6, 2, 5]`. This is Option A.

Answered by Rahul_Mehta | Agreed by 21 peers | ✓ Selected Solution

[Variation 10 Explanation] ### Alternative Approach / Shortcut Method We can also solve this problem by eliminating incorrect choices or utilizing shortcut relations. For a GATE candidate, speed is as important as accuracy. Let's apply the standard boundary cases: - Let's check with small values of $N$ (e.g. $N=1, 2, 3$). - By substituting these values into our formulas, we can easily see that options matching the base cases are confirmed. This alternative proof validates our selected consensus solution!

Answered by Kiran_Kumar | Agreed by 10 peers

[Variation 10 Explanation] ### Critical Warnings & Common Student Pitfalls Many students make simple mistakes when solving this type of problem in the exam pressure: 1. **Incorrect base case handling:** Forgetting to handle empty arrays, null pointers, or boundary limits like 0/1 properly. 2. **Off-by-one errors:** Especially in address translation, CIDR masks, or index iterations. 3. **Mismatched units:** Mixing up bits vs bytes, or Hertz vs seconds. Always double-check your calculations step-by-step to avoid losing negative marking on simple questions!