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The Journal

Practical SQL, Python, data science and AI guides, written from real practice — not just to rank.

DSA

Trie in Python: Prefix Search Explained

Trie in Python explained: insert, search, starts_with, autocomplete and wildcard search with a prefix tree, with real output.

September 26, 2026 12 min read
DSA

Backtracking in Python: Subsets and Permutations

Backtracking in Python explained: the choose, explore, undo template with subsets, permutations, combination sum, N-Queens and brackets.

September 26, 2026 13 min read
DSA

Heap and heapq in Python: Priority Queues

Heap and heapq in Python explained: push, pop, heapify, max-heap trick, top-k, priority queues, median and Dijkstra, with…

September 26, 2026 13 min read
DSA

Dynamic Programming in Python for Beginners

Dynamic programming in Python for beginners: memoization, tabulation, coin change, house robber, knapsack and LCS, with real output.

September 26, 2026 13 min read
DSA

Recursion in Python Explained Simply

Recursion in Python explained simply: base case, call stack, factorial, Fibonacci with memoization, Tower of Hanoi and the…

September 26, 2026 12 min read
DSA

Sorting Algorithms in Python: Bubble to Merge

Sorting algorithms in Python: sorted() and sort(), then bubble, selection, insertion, merge and quick sort with real comparison…

September 26, 2026 14 min read
DSA

Binary Search in Python: 3 Common Variations

Binary search in Python explained: the classic loop, first and last occurrence, insertion position, bisect and search on…

September 26, 2026 13 min read
DSA

Graphs in Python: Adjacency List, BFS and DFS

Graphs in Python explained: adjacency list and matrix, BFS, DFS, shortest path, islands, cycles and topological sort, with…

September 26, 2026 15 min read
DSA

Binary Search Tree in Python From Scratch

Binary search tree in Python from scratch: insert, search, delete, inorder, validate a BST and why balance matters,…

September 26, 2026 13 min read
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