Problem Detail: I have two questions regarding nullable nonterminals in a grammar. Often a simple algorithm is described to find nullable nonterminals: Basis: if $A rightarrow epsilon$ is a production, $A$ is nullable. Induction: if $A rightarrow X_1X_2ldots X_n$ is a Read More …
Author: ignougroup
[Solved]: Kleene plus in Thompson’s construction
Problem Detail: Is there a direct way to represent Kleene plus(+) using Thompson’s construction algorithm? When I studied Thompson’s construction I learned how to transform concatenation, union and kleene star of regular expresions directly into a NFA. In wikipedia(and other websites) Read More …
[Solved]: Origin of the terms “safety” and “liveness” for concurrent algorithm properties?
Problem Detail: Properties of concurrent algorithms are usually divided into two categories: Safety – something must not happen. Properties in this category are for example partial correctness and sometimes deadlock-freedom (the latter depending on the author). Liveness – something that must Read More …
[Solved]: Depth first or breadth first ordering in binary search trees?
Problem Detail: Let’s say that I make a binary search tree and store it in an array so that I end up with an array that is more cache friendly to binary search compared to a sorted array. The binary tree Read More …
[Solved]: Exploring and interpolating a function using machine-learning?
Problem Detail: Which general machine-learning methods are there that try to “learn” or interpolate a smooth multivariate function and which get to actually choose the points at which the function is evaluated during the learning process (exploration)? The idea would be Read More …
[Solved]: Complexity classes pertaining to listing all solutions?
Problem Detail: I was reading a question over at Stack Overflow asking whether it was NP-hard to list all simple cycles in a graph containing a particular node and it occurred to me that I couldn’t think of any existing complexity Read More …
[Solved]: What is the relation between NC and P/poly?
Problem Detail: I am unable to see a clear explanation of how the classes NC and P/poly intersect or not. (and if they do intersect then how and where? and if not then what is the proof?) Asked By : user6818 Answered Read More …
[Solved]: Enumerate All Possible Strings Over Alphabet
Problem Detail: I am given the following decision problem: A program $ Pi $ takes as input a pair of strings and outputs either $true$ or $false$. It is guaranteed that $Pi$ terminates on any input. Does there exist a pair Read More …
[Solved]: Efficiently selecting the median and elements to its left and right
Problem Detail: Suppose we have a set $S = { a_1,a_2,a_3,ldots , a_N }$ of $N$ coders. Each Coders has rating $R_i$ and the number of gold medals $E_i$, they had won so far. A Software Company wants to hire exactly Read More …
[Solved]: The $text{k-key}$ problem
Problem Detail: Given an undirected graph, I define a structure called k-key as a path containing $k$ vertices which are connected to a simple cycle which contains $k$ vertices as well. Here’s the k-key problem: given an undirected graph $G$ and Read More …
