Problem Detail: Given a context-free grammar, is there an algorithm to determine if the CFG will ever produce an even length string? Or is this undecidable? Asked By : ASDF Answered By : Hendrik Jan Of course there is a meta-algorithm via automata Read More …
Author: ignougroup
Reducing the integer factorization problem to an NP-Complete problem
Problem Detail: I’m struggling to understand the relationship between NP-Intermediate and NP-Complete. I know that if P != NP based on Lander’s Theorem there exists a class of languages in NP but not in P or in NP-Complete. Every problem in Read More …
Concrete and simple applications for bipartite graphs
Problem Detail: I am looking for concrete and simple problems that may be solved using bipartite graphs or bipartite graph properties. Any idea along with explanations are welcome. Asked By : Laurent Answered By : John Bupit Assignment Problem would be one such Read More …
How do people measure performance overhead?
Problem Detail: How do people measure performance overhead? Whenever someone is bragging about how their program or application performs better than another, they talk about particular measurements, eg time, performance etc. Whilst I understand how time to perform a task can Read More …
What is the relation between functors in SML and Category theory?
Problem Detail: Along the same thinking as this statement by Andrej Bauer in this answer The Haskell community has developed a number of techniques inspired by category theory, of which monads are best known but should not be confused with monads. Read More …
Grammar for ${a^n b^n c^{n+m}}$
Problem Detail: Can we define a grammar for the following language? $$L = {a^n b^n c^{n+m} | n,m>=0},. $$ I can define one for this: $$L={a^nb^n|n,m>=0} $$ S –> aSb | λ or this one: $$L={b^nc^{n+m}|n,m>=0} $$ S –> Ac A Read More …
In what sense is the Mandelbrot set “computable”?
Problem Detail: The Mandelbrot set is a beautiful creature in Mathematics. There are a lot of beautiful images of this set created with high precision, so obviously this set is “computable” in some sense. However, what concerns me is the fact Read More …
When inserting into a binary tree, is there a universal agreed upon place to insert then new node to minimize complexity?
Problem Detail: Do programmers (in real life), always insert at the top node or somewhere else? Because in my text book CLRS it is not made very clear, so the insertion process can take a best case of O(1), if you Read More …
How to make a language homoiconic
Problem Detail: According to this article the following line of Lisp code prints “Hello world” to standard output. (format t “hello, world”) Lisp, which is a homoiconic language, can treat code as data in this way: Now imagine that we wrote Read More …
Which NP-Complete problem has the fastest known algorithm?
Problem Detail: In terms of worst-case asymptotic runtime, which NP-complete problem has the fastest-known (exact) algorithm and what is the algorithm? Is there something known that is faster than $O(n^2*2^n)$? Asked By : Wuschelbeutel Kartoffelhuhn Answered By : Pål GD Vertex Cover has Read More …
