Tag: Sorting

4 posts

May 25, 2026 24 min read Beginner

Bubble, Selection and Insertion Sort: Time Complexity and Why Insertion Sort Wins on Nearly Sorted Data

Bubble, selection and insertion sort in Python with their time complexity, why insertion sort wins on nearly sorted data, and how Timsort fits in.
May 25, 2026 20 min read Intermediate

Quick Sort, Merge Sort and Heap Sort: How O(n log n) Sorting Works and When Each Wins

Quick, merge and heap sort in Python: how each reaches O(n log n), when quick sort degrades to O(n^2), which are stable or in-place, and Kth largest.
May 25, 2026 17 min read Beginner

Sorting Problems: Multi-Key Sorts, Custom Comparators, and When Sorting First Solves the Problem

Sorting interview problems in Python: stable multi-key sorts, cmp_to_key comparators, why sort-by-end greedy works, and comparator bugs that fail submissions.
May 25, 2026 20 min read Intermediate

Binary Search: Lower/Upper Bound, Binary Search on the Answer, and Off-by-One Traps

Binary search beyond "find x in a sorted array": loop invariants that keep bounds correct, lower and upper bound, binary search on the answer, and the off-by-one and infinite-loop bugs that fail interviews.