Problem Detail: Is the grammar $qquad S to 1A0A mid 0A mid varepsilon$ a right-linear grammar? $A$ is a nonterminal here, $0$ and $1$ are terminals. I know $0A$ is right-linear but what about $1A0A$? Trying to construct a right-linear grammar Read More …
Category: Uncategorized
[Solved]: Can $emptyset$ be reducible to any other language?
Problem Detail: While solving some question, that involved the empty set $emptyset$, I was really wondering, is $emptyset$ reducible to any other language, i.e., $emptyset leq A$ such that $A$ is a language over a given alphabet $Sigma^*$? I mean, one Read More …
[Solved]: Heuristics for an Artificial Intelligence problem
Problem Detail: Problem : Given a (one dimensional) row containing $2N$ tiles arranged in $2N + 1$ spaces. There are $N$ black tiles (B), $N$ white tiles (W), and a single empty space. The tiles are initially in an arbitrary Read More …
[Solved]: Is every algorithm’s complexity $Omega(1)$ and $O(infty)$?
Problem Detail: From what I’ve read, Big O is the absolute worst ever amount of complexity an algorithm will be given an input. On the side, Big Omega is the best possible efficiency, i.e. lowest complexity. Can it be said then Read More …
[Solved]: Classfication of randomized algorithms
Problem Detail: From Wikipedia about randomized algorithms One has to distinguish between algorithms that use the random input to reduce the expected running time or memory usage, but always terminate with a correct result in a bounded amount of time, and Read More …
[Solved]: Are the words “expression” and “term” interchangeable in programming language theory?
Problem Detail: When describing the syntax of a given programming language the words “expression” and “term” are often used to seemingly describe the same things. Are these words interchangeable in the context of programming languages? Asked By : tibbe Answered By : Gilles Read More …
[Solved]: How are REGEXP implemented in programming languages?
Problem Detail: Is there a good general paper about the interpretation or compilation of REGEXP in programming languages for pattern matching, with or without variables? I am not looking for a quick explanation about the construction of DFAs, but for a Read More …
[Solved]: Difference between regular expressions: $(0^*1^*)^*$ and $(0+1)^*$
Problem Detail: Can anyone tell me what is the difference between the following regular expressions: $(0^*1^*)^*$ and $(0+1)^*$ ? To me they look like generating the same string. Asked By : Abhishek Anand Answered By : Ran G. The language of both regular Read More …
[Solved]: Chomsky normal form and regular languages
Problem Detail: I’d love your help with the following question: Let $G$ be context free grammar in the Chomksy normal form with $k$ variables. Is the language $B = { w in L(G) : |w| >2^k }$ regular ? What is Read More …
[Solved]: Space complexity below $loglog$
Problem Detail: Show that for $l(n) = log log n$, it holds that $text{DSPACE}(o(l)) = text{DSPACE}(O(1))$. It’s well known fact in Space Complexity, but how to show it explicitly? Asked By : com Answered By : A.Schulz So here is the main idea Read More …
