Many hard LeetCode problems are easy constraint problems
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Many hard LeetCode problems are easy constraint problems
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Re: Many hard LeetCode problems are easy constraint problems
#2Use the right tool for the right job!
Re: Many hard LeetCode problems are easy constraint problems
#3I feel like if I'm being asked this in an interview, they're not asking me to use a constraint solver, they're asking me to _write_ a constraint solver. Just for a specific constraint problem, not a more general constraint solver.
Re: Many hard LeetCode problems are easy constraint problems
#4I feel like if I'm being asked this in an interview, they're not asking me to use a constraint solver, they're asking me to _write_ a constraint solver. Just for a specific constraint problem, not a more general constraint solver.
Yes and no: I've asked questions like this in interviews, and I'd count it as a plus if the candidate reached for a constraint solver. They're criminally underused in real-world software engineering and this would show the candidate probably knows how to get the right answer faster instead of wasting a bunch of time.
Now, if they did answer with a constraint solver, I'd probably ask some followup whiteboard questions to make sure they do actually know how to code. But just giving a constraint solver as an answer definitely wouldn't be bad.
Re: Many hard LeetCode problems are easy constraint problems
#5Great insight. But this is sadly not applicable to interviews.
> It's easy to do in O(n^2) time, or if you are clever, you can do it in O(n). Or you could be not clever at all and just write it as a constraint problem
This nails it. The point of these problems is to test your cleverness. That's it. Presenting a not-clever solution of using constraint solvers shows that you have experience and your breadth of knowledge is great. It doesn't show any cleverness.
Re: Many hard LeetCode problems are easy constraint problems
#6I feel like if I'm being asked this in an interview, they're not asking me to use a constraint solver, they're asking me to _write_ a constraint solver. Just for a specific constraint problem, not a more general constraint solver.
Yes and no: I've asked questions like this in interviews, and I'd count it as a plus if the candidate reached for a constraint solver. They're criminally underused in real-world software engineering and this would show the candidate probably knows how to get the right answer faster instead of wasting a bunch of time. Now, if they did answer with a constraint solver, I'd probably ask some followup whiteboard questions…
General constraint solver would be terribly inefficient for problems like these. It's a linear problem and constraint solver just can't handle O(10^6) variables without some beefy machine.
Re: Many hard LeetCode problems are easy constraint problems
#7Great insight. But this is sadly not applicable to interviews. > It's easy to do in O(n^2) time, or if you are clever, you can do it in O(n). Or you could be not clever at all and just write it as a constraint problem This nails it. The point of these problems is to test your cleverness. That's it. Presenting a not-clever solution of using constraint solvers shows that you have experience and your breadth of knowledg…
The point is to test whether or not you put in the time to sharpen common patterns and also to test your communication ability
Re: Many hard LeetCode problems are easy constraint problems
#8Most interviews are based on the premise that if a diabetic can't synthesize their own insulin in their basement, they are somehow cheating at the game of life.
If my wife's blood sugar is high, she takes insulin. If you need to solve a constraint problem, use a constraint solver.
If your company doesn't make and sell constraint solving software, why do you need me to presume that software doesn't exist and invent it from scratch?
Re: Many hard LeetCode problems are easy constraint problems
#9I avoided all this just by becoming a contractor, i ship solution, no me tests me for leetcode ability
Re: Many hard LeetCode problems are easy constraint problems
#10Earlier quoted context omitted.
Yes and no: I've asked questions like this in interviews, and I'd count it as a plus if the candidate reached for a constraint solver. They're criminally underused in real-world software engineering and this would show the candidate probably knows how to get the right answer faster instead of wasting a bunch of time. Now, if they did answer with a constraint solver, I'd probably ask some followup whiteboard questions…
General constraint solver would be terribly inefficient for problems like these. It's a linear problem and constraint solver just can't handle O(10^6) variables without some beefy machine.
Okay, but who says you need to use a simple constraint solver? There are various sophisticated constraint solvers that know how to optimize.
At this point, job interviews are so far removed from actual relevance. Experience and aptitude still matter a lot, but too much experience at one employer can ground people in rigid and limiting ways of thinking and solving problems.