VisuAlgo
visualgo.net
Animated, step-by-step visualisations of data structures and algorithms, from sorting and linked lists to graphs and dynamic programming, with the ability to run each on your own input.
VisuAlgo was started in 2011 by Steven Halim at the National University of Singapore so his students could learn data structures and algorithms at their own pace. Each topic has an animated visualisation that steps through the algorithm, highlights what changes at every stage, and lets you run it on your own input or on random data.
Coverage runs from sorting, linked lists and heaps to graph algorithms and dynamic programming. The explanatory text and optional practice quizzes sit alongside the animations. It works best as a companion to a textbook or lecture: watching an algorithm move step by step makes the logic much easier to follow than static diagrams.
Why it is useful
Seeing an algorithm move one step at a time makes it far easier to understand than pseudocode alone. You can enter your own data, step forwards and backwards, and test yourself with built-in quizzes. It was created at the National University of Singapore and is free to use.
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