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Thursday Code Puzzler: Needles In the Haystack

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Thursday Code Puzzler: Needles In the Haystack

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Take 60 minutes to understand the Power of the Actor Model with "Designing Reactive Systems: The Role Of Actors In Distributed Architecture". Brought to you in partnership with Lightbend.

By now you should be familiar with our Thursday Code Puzzler slot. The idea is simple: solve the coding problem as efficiently as you can, in any language or framework that you think is suitable.

Note: Even though there really is nothing stopping you from finding a solution to this on the internet, try to keep honest, and come up with your own answer.  It's all about the participation!

Find The Needles in the Haystack

This week it's another classic string based question - to find the number of occurances of a given String (needle) in another (haystack). So the method signature would look like:

public int findNeedleOccurances(String needle, String haystack)

Try to make the solution as efficient as possible, and if you do get to run it post up your timings, or even better, the Big O notation for your solution.


Learn how the Actor model provides a simple but powerful way to design and implement reactive applications that can distribute work across clusters of cores and servers. Brought to you in partnership with Lightbend.


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