alt Hacker NewsA month ago, I went on a performance quest trying to optimize a PHP script that took 5 days to run. Together with the help of many talented developers, I eventually got it to run in under 30 seconds.
When people say leetcode interviews are pointless I might share a link to this post. If that sort of optimization is possible there is a structures and algorithms problem in the background somewhere.
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Well leetcode asks you to implement the data structure, not how and when to use which data structure. I don’t need to know how to implement a bloom filter on a whiteboard off the top of my head to know when to use it.
Do you think they achieved that performance optimisation with a networked service because they switched from insertion sort to quicksort?
I find that these kind of optimizations are usually more about technical architecture than leetcode. Last time I got speedups this crazy the biggest win was reducing the number of network/database calls. There were also optimisations around reducing allocations and pulling expensive work out of hot loops. But leetcode interview questions don't tend to cover any of that.
They tend to be about the implementation details of specific algorithms and data structures. Whereas the important skill in most real-world scenarios would be to understand the trade-offs between different algorithms and data structures so that you pick an appropriate off-the-shelf implementation to use.