Hello!
Explanation:
1 - It takes the number and converts it to an array
2 - Then the letters inside this array are converted to decimal numbers and it's returned by the first function (an array of integers)
3 - Reduce is applied to multiply each item of the array of integers by the base 16, raised to its respective pow, and make a sum of these multiplications.
Example:

• 'E5D4'
  1 - ['E', '5', 'D', '4' ]
  2 - [14, 5, 13, 4]
  3 - 14 * 16³ + 5 * 16² + 13 * 16¹ + 4 * 16⁰ = 58836

Hope this can be useful to conversions in JavaScript repository :)

Welcome to JavaScript community

Describe your change:

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• Fix a bug or typo in an existing algorithm?
• Documentation change?

Checklist:

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• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
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