Find the shortest clear path from the top-left to bottom-right of a 0-1 grid. We explain the intuition, walk through…
Author: codeanddebug
Need not just distances but the real route? Learn how to extend Dijkstra’s algorithm to reconstruct the shortest path from…
See how to run Dijkstra with a set instead of a heap. We break down the idea, walk through clear…
Learn to implement Dijkstras Algorithm with a Priority Queue using a min-heap (heapq). We cover the problem statement, clear intuition,…
Learn how to find single source shortest path in a weighted directed acyclic graph (DAG) in linear time. We explain…
Find the Shortest Path in an Undirected Graph from a source to every other node when every edge costs 1.…
Learn a one-pass way to check if array is sorted in non-decreasing order. Intuition, commented Python code, dry run, and…
Need the second smallest and second largest in one array? We compare a clear two-pass “better” method with a one-pass…
Quick Sort is a popular sorting algorithm that follows a divide-and-conquer approach. When implemented well, Quick Sort can be extremely…
Merge Sort is a classic divide-and-conquer sorting technique. It divides the list into two halves, sorts each half recursively, and…