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A comment on Ask HN: What are some important math topics every programmer should know?. Parent comment
Ever tried to delete 1 000 000 files in Windows Explorer ? Select All, Shift delete ?
Takes ages. Why ? because Explorer creates a list of files to be deleted by adding one after the other to the list while updating the screen.
del bak\[asterisk.asterisk] /S /Q /Y >NUL takes some time, but is way faster.
rmdir bak drops the entire directory and returns instantly.
The difference ? O(n^2) versus O(n) versus O(1)
Useful knowledge ? ... possibly.
Even then 'just' programming a website, winging full stack or doing anything worthwile you can get by without knowledge, but it sure helps...
P.S. how do you escape an asterisk ? Even google didn't know / i didn't find it...
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Ever tried to delete 1 000 000 files in Windows Explorer ? Select All, Shift delete ?
Takes ages. Why ? because Explorer creates a list of files to be deleted by adding one after the other to the list while updating the screen.
del bak\[asterisk.asterisk] /S /Q /Y >NUL takes some time, but is way faster.
rmdir bak drops the entire directory and returns instantly.
The difference ? O(n^2) versus O(n) versus O(1)
Useful knowledge ? ... possibly.
Even then 'just' programming a website, winging full stack or doing anything worthwile you can get by without knowledge, but it sure helps...
P.S. how do you escape an asterisk ? Even google didn't know / i didn't find it...