Problem Detail: I understand that any CFL can be accepted by a PDA by final state or empty store but I have been rather stumped by this question. The question states that the PDA has at most 2 states. Clearly 1 Read More …
Blog
Show $x^y$ is a primitive recursive function
Problem Detail: As this thread title gives away I need to prove $x^y$ to be a primitive recursive function. So mathematically speaking, I think the following are the recursion equations, well aware that I am assigning to $0^0$ the value $1$, Read More …
P-Completeness and Parallel Computation
Problem Detail: I was recently reading about algorithms for checking bisimilarity and read that the problem is P-complete. Furthermore, a consequence of this is that this problem, or any P-complete problem, is unlikely to have an efficient parallel algorithms. What is Read More …
Creating a Deterministic Push Down Automata
Problem Detail: I saw this old post on stack overflow of a PDA that accepts a language where there are exactly twice as many a’s as there are b’s. The image they used is below and so is the link to Read More …
What is a partially computable function?
Problem Detail: In the book Computability, Complexity, and Languages, Martin Davis writes in chapter two: A partial function is said to be partially computable if it is computed by some program. and also A function is said to be computable if Read More …
Is there a method for automatic runtime analysis of algorithms?
Problem Detail: I am wondering, is there a method for automatic runtime analysis that works at least on a relevant subset of algorithms (algorithms that can be analyzed)? I googled “Automatic algorithm analysis” which gave me this but it is too Read More …
How can the Operating System run on the same chip it is supposed to be managing?
Problem Detail: From my readings about Operating Systems (reading the basic material on Wikipedia, tech sites, etc) I’ve learned that the Operating System is a program that allows programs and applications to interact with the hardware in an efficient and safe Read More …
Knapsack problem, partition problem, or in general dynamic algorithm with negative numbers allowed
Problem Detail: How to think about dynamic algorithms which allows negative integers in input (where it’s problematic, because obviously it’s not always the case)? Examples: Partition Problem with negative numbers in set allowed Knapsack problem with negative weights are allowed Is Read More …
Heuristic for sokoban puzzle problem
Problem Detail: I am trying to write IDA* for Sokoban puzzle problem (http://en.wikipedia.org/wiki/Sokoban) but It seems that my heuristic is not so good for making the algorithm fast. My heuristic is to consider $h(s)$ as minimum distance between the Player and Read More …
Infinite alphabet Turing Machine
Problem Detail: Is a Turing Machine that is allowed to read and write symbols from an infinite alphabet more powerful than a regular TM (that is the only difference, the machine still has a finite number of states)? Intuition tells me Read More …
