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Binary Search

Hajar | هاجر on September 05, 2021

Binary Search is one of the fastest searching algorithms, especially when it comes to searching large (sorted) lists. The main goal of Binary Sear...

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stefnotch • Sep 7 '21

Nice explanation and congratulations on presenting an actually correct variant of binary search. 🚀

Since I believe that anything can be improved, no matter how nice it is, here is some feedback:
Issues

No parameters. list and itemToFind should very much be parameters that are passed to the function
Usage of parseInt. It's really not needed and it just causes a performance overhead.
(start + end) / 2 isn't ideal either, since with large enough arrays, this can cause some overflowing/rounding. The improved variant is start + ((end - start ) / 2) Might be interesting to note
An alternative to return -1 is return -start. Then, the negative return value would point at the smallest element that's >= itemToFind. And that's pretty useful when one wants to insert a new element.

Hajar | هاجر • Sep 8 '21

Thank you so much for your feedback @stefnotch . 😀
I fixed the no-parameters issue but am curious, why do you think that parseInt isn't needed here? Aren't we using it to avoid having fractions in the middle index? 🤔

stefnotch • Sep 12 '21

I see, I missed that detail!

Although, parseInt is not designed for that. It's purpose is to turn a string (text) into a number. If the intention is to chop off the fractional part, then Math.floor is the standard function to use.
e.g. start + Math.floor((end - start) / 2)