DSA · Theory

Difference between Stack and Heap

Theory

78/810

Difference between Stack and Heap

Difference between Stack and Heap is a DSA topic. In plain words you use it for undo typing in a tiny editor. Don’t start with a slogan — start with that picture.

Smallest example: push / pop LIFO. Type it, run it, and say what you see. If you can do that from memory, you know Difference between Stack and Heap.

From the example next to this theory: Difference between Stack and Heap — heap sort uses a binary heap to repeatedly extract the minimum.

Trap — pop on empty. Fix that before you talk about advanced DSA.

Viva — what is Difference between Stack and Heap? Then show push / pop LIFO. Then name the trap.

Diagram

    | 3 |  ← top (pop)
    | 2 |
    | 1 |
    LIFO

Exam tip

What is Difference between Stack and Heap? Show this: push / pop LIFO. Trap: pop on empty.

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]))

Difference between Stack and Heap — heap sort uses a binary heap to repeatedly extract the minimum.

Short notes

DefDifference between Stack and Heap — undo typing in a tiny editor.
Rulepush / pop LIFO
Trappop on empty
Usea tiny editor

DSA · Theory

Difference between Stack and Heap

← All stacks

Theory

78/810

Difference between Stack and Heap

Difference between Stack and Heap is a DSA topic. In plain words you use it for undo typing in a tiny editor. Don’t start with a slogan — start with that picture.

Smallest example: push / pop LIFO. Type it, run it, and say what you see. If you can do that from memory, you know Difference between Stack and Heap.

From the example next to this theory: Difference between Stack and Heap — heap sort uses a binary heap to repeatedly extract the minimum.

Trap — pop on empty. Fix that before you talk about advanced DSA.

Viva — what is Difference between Stack and Heap? Then show push / pop LIFO. Then name the trap.

Diagram

    | 3 |  ← top (pop)
    | 2 |
    | 1 |
    LIFO

Exam tip

What is Difference between Stack and Heap? Show this: push / pop LIFO. Trap: pop on empty.

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]))

Difference between Stack and Heap — heap sort uses a binary heap to repeatedly extract the minimum.

Short notes

DefDifference between Stack and Heap — undo typing in a tiny editor.
Rulepush / pop LIFO
Trappop on empty
Usea tiny editor

Difference between Stack and Heap

Example

Short notes

Questions

Difference between Stack and Heap

Example

Short notes

Questions