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Problem Detail: Here’s something that has puzzled me lately, and perhaps someone can explain what I’m missing. Problems in NP are those that can be solved on a NDTM in polynomial time. Now assuming P$,neq,$NP, PSPACE$,neq,$NP etc. this means that there Read More …

Problem Detail: In studying logic to understand verifying programs I have found that there are books on logic targeted at Computer Science e.g. Logic in Computer Science: Modelling and Reasoning about Systems Mathematical Logic for Computer Science Computability and Logic Handbook Read More …

Problem Detail: Is the jury still out on this or do we now know which of the above mentioned ways of randomizing Quick Sort is the most optimum as far as average case running time (averaged over all possible input arrays, Read More …

Problem Detail: I have a question about definability of truth assignments. Suppose that I am working in the context of propositional logic. Let me give some definitions first. Let $L$ be a propositional language with the set $Prop_{L}$ of propositional variables. Read More …

Problem Detail: I’ve been reading Sedgewick’s intro to algorithms book, and he says that the reverse postorder of a digraph’s reverse is not the same as the postorder of the digraph, however in both cases it seems that we get the Read More …

Problem Detail: Assume ${f_i^{(n)}}_{i=0}^infty$ is a Gödel enumeration of the $mu$-recursive functions of $n$ arguments, such that the $S^m_n$ theorem and the universal function theorem hold. Denote the set of (total and partial) functions ${f:mathbb N^ktomathbb N }$ by $mathfrak F^k$ Read More …

Problem Detail: I am teaching myself algorithms with the online lecture notes by Jeff Erickson and fails to solve the following problem (Problem 21 of Lecture 1). (a) Describe an algorithm that sorts an input array $A[1 ldots n]$ by calling Read More …

Problem Detail: When training a classifier for object detection using features extracted from images (eg HoG features), how important is it that the images used for training fed into the classifier in their natural aspect ratio? For example, regardless of their Read More …

Problem Detail: The usual statement of the fair cake-cutting problem assumes that all $n$ players get their share at the same time. However, in many cases the players arrive incrementally. For example, we may divide a cake over $n$ players, but Read More …

Problem Detail: Where should I look for a good introductory text in algorithm complexity? So far, I have had an Algorithms class, and several language classes, but nothing with a theoretical backbone. I get the whole complexity, but sometimes it’s hard Read More …