DSA · Theory

Time Complexity of building a heap

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Theory

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Time Complexity of building a heap

Time Complexity of building a heap is simple if you keep it on paper. Zara uses it for next patient in a clinic.

Time Complexity of building a heap on the board: heapify + extract. Then say what next patient looks like after.

Skip Time Complexity of building a heap and min-heap vs max-heap mix-up shows up in a clinic.

Use Time Complexity of building a heap when next patient must stay clear. If a simpler DSA step works, use that instead.

Time Complexity of building a heap trap — min-heap vs max-heap mix-up. Zara loses marks for that every viva.

Place Time Complexity of building a heap next to nearby DSA work — heapify + extract is the link.

Close Time Complexity of building a heap with: “If I skip it, next patient goes wrong like this: min-heap vs max-heap mix-up.”

Exam tip

Say Time Complexity of building a heap in one breath, then heapify + extract, then min-heap vs max-heap mix-up.

Example

import heapq

def heap_sort(arr):
    h = arr[:]
    heapq.heapify(h)
    return [heapq.heappop(h) for _ in range(len(h))]

print(heap_sort([5, 1, 4, 2]))

Time Complexity of building a heap — heap sort uses a binary heap to repeatedly extract the minimum.

Short notes

DefTime Complexity of building a heap — Zara uses it for next patient in a clinic.
RuleTime Complexity of building a heap → heapify + extract.
RememberTime Complexity of building a heap + a dry-run table (a clinic).
UseTime Complexity of building a heap in a clinic (next patient).
TrapTime Complexity of building a heap — min-heap vs max-heap mix-up.
ExTime Complexity of building a heap → next patient.

DSA · Theory

Time Complexity of building a heap

← All stacks

Theory

530/810

Time Complexity of building a heap

Time Complexity of building a heap is simple if you keep it on paper. Zara uses it for next patient in a clinic.

Time Complexity of building a heap on the board: heapify + extract. Then say what next patient looks like after.

Skip Time Complexity of building a heap and min-heap vs max-heap mix-up shows up in a clinic.

Use Time Complexity of building a heap when next patient must stay clear. If a simpler DSA step works, use that instead.

Time Complexity of building a heap trap — min-heap vs max-heap mix-up. Zara loses marks for that every viva.

Place Time Complexity of building a heap next to nearby DSA work — heapify + extract is the link.

Close Time Complexity of building a heap with: “If I skip it, next patient goes wrong like this: min-heap vs max-heap mix-up.”

Exam tip

Say Time Complexity of building a heap in one breath, then heapify + extract, then min-heap vs max-heap mix-up.

Example

import heapq

def heap_sort(arr):
    h = arr[:]
    heapq.heapify(h)
    return [heapq.heappop(h) for _ in range(len(h))]

print(heap_sort([5, 1, 4, 2]))

Time Complexity of building a heap — heap sort uses a binary heap to repeatedly extract the minimum.

Short notes

DefTime Complexity of building a heap — Zara uses it for next patient in a clinic.
RuleTime Complexity of building a heap → heapify + extract.
RememberTime Complexity of building a heap + a dry-run table (a clinic).
UseTime Complexity of building a heap in a clinic (next patient).
TrapTime Complexity of building a heap — min-heap vs max-heap mix-up.
ExTime Complexity of building a heap → next patient.

Time Complexity of building a heap

Example

Short notes

Questions

Time Complexity of building a heap

Example

Short notes

Questions