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Problem Detail: I’m currently taking a class in Automata Theory and it’s kicking my butt. I have an assignment that my teacher gave me that consists of three questions. I have no idea where to start. My teacher and I have Read More …

Problem Detail:  You are given a tree $T=(V,E)$ along with a designated root node $r in V$.The parent of any node $v ne r$, denoted $p(v)$, is defined to be the node adjacent to $v$ in the path from $r$ Read More …

Problem Detail: Are there any graph implementation data structures beyond the standard adjacency list/matrix ones? If so, what are they? I welcome experimental ones as well as highly specialized ones. A little background: I’m developing an algorithm that relies heavily on Read More …

Problem Detail: I am little bit confused between the two answers below. What is the exact answer of this question? My query is, “Deleted data remains on a disk until…?” The data is overwritten; The recycle bin is emptied. I have Read More …

Problem Detail: I am working through Sipser, and I am trying to understand some of the algorithms described in Space Complexity, but I am having a hard time understanding the presentation of the material (especially Savitch’s theorem). I have a very Read More …

Problem Detail: I want to prove that unique(reverse(L)) = reverse(unique(L)) where L is a List. List has the following constructors: [] : -> List [e] : Element -> List cons(e, L) : Element x List -> List I defined unique and Read More …

Problem Detail: I am attempting to write a Finite State Transducer module in OCaml, because I think it’s a good exercise, which is because I have been teaching myself Natural Language Processing. You typically construct finite automata using regular expressions, for Read More …

Problem Detail: Let’s say that lists are defined as List a = Nil | Cons a (List a) Then, in Haskell is List x the greatest or least fixpoint? I’m asking because the lfp should exclude infinite lists (but you can Read More …

Problem Detail: I’m having trouble wrapping my head around the problems PRIME, COMPOSITE, FACTOR and how they’re related in terms of complexity. I understand that PRIME has been shown to be in $P$ by the AKS primality test, and I believe Read More …

Problem Detail: I am trying to solve the following problem: For each Turing machine $M_k$ and each string $x$ in ${$0,1$}$$^ast$ let $time_k(x)$ = ${$the number of steps executed by $M_k(x)$ if $M_k(x)$$downarrow$ (halts), and $infty$ if $M_k(x)$$uparrow$ (does not halt)$}$ Read More …