• magic_lobster_party@fedia.io
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    6 days ago

    The quadratic equation is the basis for most other math and physics. It’s used all the time.

    The good thing about quicksort is that it’s a good demonstration of an O(n log n) algorithm, and that’s about it.

    • Captain Aggravated@sh.itjust.works
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      5 days ago

      “The basis for most other math and physics” they do a complete fucksewage job at demonstrating that in school. I remember several years in math class “And here’s the quadratic equation, the one that’s all over 2a” and it was an exercise in plugging and chugging.

      Math is a useful, powerful and allegedly beautiful thing. it’s such a shame it’s illegal to teach it competently.

    • Kidplayer_666@lemm.ee
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      6 days ago

      If I’m not mistaken, quick sort is worst case O(n^2), merge sort is what actually achieves O(nlogn), the point is that quicksort is on average more memory (and time?) efficient

      • magic_lobster_party@fedia.io
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        5 days ago

        Maybe.

        When using a random pivot, the worst case becomes exponentially more unlikely the larger the n. The O notation only cares about the complexity when n approaches infinity. So when n approaches infinity, the likelihood of O(n^2) performance approaches 0 (and the likelihood of O(n log n) approaches 1).

        I think it’s fine to call it O(n log n).