I got a new job and finally getting ready to move out of my parents' house, but my god rent is comically expensive where I'm at (like everywhere else). There aren't many places to look for roommates outside of craigslist (which I'm trying to avoid). It's looking like I might have to spend close to 40% of my paycheck to afford a 500 sq foot studio
They say you throw away communism when you get your first salaried job, but I think it's making me a third world maoist. Fuck all landlords
How important is it to learn Data structures and Algorithms if I wanna land a job?
That's one of the more important ones I'd say — in particular because many technical interviews are focused on DS&A.
For practical purposes in my experience as long as you have a sense of what's going to be slow in your program and you know how to use a hash (aka hashmap or dictionary) and an array (aka list) and know what a binary tree is you'll do just fine on most jobs.
I've never sat down and tried to figure out the big-O notation of anything I've been paid to write — it doesn't matter cause the slowest thing is always going to be a web request or an expensive database query, and that's going to be true for basically any web engineering jobs (which are the plurality if not majority of jobs these days)
How do I get this sense? Practice?
yeah, mostly — this chart helps a bit: https://gist.github.com/jboner/2841832
I wouldn't worry about committing the exact numbers to memory, or remembering the order of some of the low-level operations. Basically "reading something in memory is fast, reading something from disk slightly slower, reading something across the network even slower than that"