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Discussion on: JavaScript Interview: Write a custom reduce function

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kennethlum profile image
Kenneth Lum

The current solution right now as of May 20, 2021, is that it uses function customReduce(arr, reducer, initialValue = 0) { which is to assume initialValue is 0, but it can't always be the case.

[1,3,5].reduce((a,b) => a * b)   // => 15
customReduce([1,3,5], (a,b) => a * b)   // => 0
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so essentially, one way is that when there is no initial value, we'd use the first value as the initial value instead.

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amitkhonde profile image
Amit Khonde Author

Thank you for pointing out Kenneth. Will edit that part definitely.