Problem Detail: I’m having trouble intuitively understanding why PSPACE is generally believed to be different from EXPTIME. If PSPACE is the set of problems solvable in space polynomial in the input size $f(n)$, then how can there be a class of Read More …
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difference between multilayer perceptron and linear regression
Problem Detail: What is the difference between multilayer perceptron and linear regression classifier. I am trying to learn a model with numerical attributes, and predict a numerical value. Thanks Asked By : user20287 Answered By : Peter If you have a neural network Read More …
Differences between the Actor Model and Communicating Sequential Processes (CSP)
Problem Detail: When we look at the Actor Model and Communicating Sequential Processes we see that they are both trying to do concurrency based on message passing, yet they are distinct. (We see implementations of the CSP Model in go-lang‘s goroutines Read More …
NP completeness proof of a spanning tree problem
Problem Detail: I am looking for some hints in a question asked by my instructor. So I just figured out this decision problem is $sf{NPtext{-}complete}$: In a graph $G$, is there a spanning tree in $G$ that contain an exact set Read More …
How do garbage collectors avoid stack overflow?
Problem Detail: So I was thinking about how garbage collectors work and I thought of an interesting issue. Presumably garbage collectors have to traverse all structures in the same way. They can’t know weather they are traversing a linked list or Read More …
Algorithmic intuition for logarithmic complexity
Problem Detail: I believe I have a reasonable grasp of complexities like $mathcal{O}(1)$, $Theta(n)$ and $Theta(n^2)$. In terms of a list, $mathcal{O}(1)$ is a constant lookup, so it’s just getting the head of the list. $Theta(n)$ is where I’d walk the Read More …
Can regular languages be Turing complete?
Problem Detail: I was reading about Iota and Jot and found this section confusing: Unlike Iota, where the syntactic tree for a string can branch either on the left or on the right, Jot syntax is uniformly left-branching. As a result, Read More …
Is the halting problem decidable for pure programs on an ideal computer?
Problem Detail: It’s fairly simple to understand why the halting problem is undecidable for impure programs (i.e., ones that have I/O and/or states dependent on the machine-global state); but intuitively, it seems that a pure program’s halting on an ideal computer Read More …
Is every regular language Turing-decidable, and how can we prove this?
Problem Detail: I know every regular language is Turing-acceptable, but does that imply it is Turing-decidable? Asked By : Iancovici Answered By : Mandar Mitra Every regular language is Turing-decidable and therefore Turing acceptable / recognisable (but note that Turing acceptable does not Read More …
Proving a binary tree has at most $lceil n/2 rceil$ leaves
Problem Detail: I’m trying to prove that a binary tree with $n$ nodes has at most $leftlceil frac{n}{2} rightrceil$ leaves. How would I go about doing this with induction? For people who were following in the original question about heaps, it Read More …
