Python · Theory

Sorting Algorithms in Python

Theory

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Sorting Algorithms in Python

Sorting Algorithms orders a list. Say the idea in plain words, then complexity. Bubble/insertion/selection are O(n²) teaching sorts. Merge and heap are O(n log n). Python’s built-in sort is Timsort (O(n log n), very fast in practice).

Dry-run Sorting Algorithms on a tiny list like [4, 1, 3, 2] on the board. Interviewers care that you can trace one pass, not that you recite a textbook page.

For Sorting Algorithms in real code: sorted(a) / a.sort() is what you use. Write the algorithm only when they ask you to implement it.

Sorting Algorithms in Python — output — [1, 2, 3, 4] twice. sorted new list; sort in place.

Exam tip

Idea + complexity + one tiny trace. Then say when to use built-in sort.

Example

# Sorting Algorithms in Python
print(sorted([4, 1, 3, 2]))
a = [4, 1, 3, 2]
a.sort()
print(a)

Sorting Algorithms in Python — output: [1, 2, 3, 4] twice. sorted new list; sort in place.

Short notes

DefSorting Algorithms puts items in order.
RuleSorting Algorithms — know idea + O(...).
RememberSorting Algorithms — real code uses sorted() / Timsort.
TrapSorting Algorithms — implementing O(n²) in production when sorted() exists.

Python · Theory

Sorting Algorithms in Python

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Theory

77/268

Sorting Algorithms in Python

Dry-run Sorting Algorithms on a tiny list like [4, 1, 3, 2] on the board. Interviewers care that you can trace one pass, not that you recite a textbook page.

For Sorting Algorithms in real code: sorted(a) / a.sort() is what you use. Write the algorithm only when they ask you to implement it.

Sorting Algorithms in Python — output — [1, 2, 3, 4] twice. sorted new list; sort in place.

Exam tip

Idea + complexity + one tiny trace. Then say when to use built-in sort.

Example

# Sorting Algorithms in Python
print(sorted([4, 1, 3, 2]))
a = [4, 1, 3, 2]
a.sort()
print(a)

Sorting Algorithms in Python — output: [1, 2, 3, 4] twice. sorted new list; sort in place.

Short notes

DefSorting Algorithms puts items in order.
RuleSorting Algorithms — know idea + O(...).
RememberSorting Algorithms — real code uses sorted() / Timsort.
TrapSorting Algorithms — implementing O(n²) in production when sorted() exists.

Sorting Algorithms in Python

Example

Short notes

Questions

Sorting Algorithms in Python

Example

Short notes

Questions