Add Data Structures and Algorithms Visualizer link

[coshubhamde]

Added the link to a very useful website for visualisation of data structure and algorithms with prebuilt options to choose the operation ( insert, create, traverse, search etc.) to be performed, for the chosen data structure or algorithm with customised inputs, giving a perfect playground for learners to grasp the concept of a data structure or working of an algorithm.

What does this PR do?

Add resource(s)

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Description

Why is this valuable ?

It solves the problem of beginners who find it difficult to understand codes through dry run and have difficulty in grasping data structure concepts only through theory. The visualisation of the working of a data structure or algorithm which is chosen by the learner and then the operation and later the inputs, makes it much easier to understand these concepts and provides customised learning experience to the learner.

How do we know it's really free?

No login required, just access the website and use.

Checklist:

• Search for duplicates.
• Include author(s) and platform where appropriate.
• Put lists in alphabetical order, correct spacing.
• Add needed indications (PDF, access notes, under construction).
• Used an informative name for this pull request.

Follow-up

• Check the status of GitHub Actions and resolve any reported warnings!

[github-actions]

Linter failed, fix the error(s):

free-programming-books/more/free-programming-playgrounds.md
61:1-63:63  warning  Alphabetical ordering: swap l.62 and l.61  alphabetize-lists  remark-lint

[eshellman]

Suggested change

	* [Data Structures and Algorithms Visualizer](https://visualgo.net/en)
	* [visualising data structures and algorithms through animation](https://visualgo.net/en)

Don't invent titles! Use the title given by the resource.

[coshubhamde]

Thanks @eshellman for pointing that out. Implemented your suggested change.