Blog

Problem Detail: According to my understanding, a Turing machine that’s valid has to have finite steps to finish a certain step. If this is right, what else determines the validity of a turing machine? Asked By : Shelby. S Answered By : Jonathan Read More …

Problem Detail: Is it practically possible or even near possible to make parity game to be solved in polynomial time? If yes, how? and if No, why? Asked By : Andy Answered By : Shaull Parity games are famously known to be in Read More …

Problem Detail: So, I have a list of cities (A, B, C, etc) with weighted edges (two-way, undirected) between them with a list of cities that already have a store. My task is to place a one new store at either Read More …

Problem Detail: The problem, coming from an interview question, is: You have a stream of incoming numbers in range 0 to 60000 and you have a function which will take a number from that range and return the count of occurrence Read More …

Problem Detail: I am trying to define a Odd Parity Function that takes three 1 bit inputs and will output a 1 if the 3 bits are odd as a Boolean function. 1 1 0 = 0 1 0 0 = Read More …

Problem Detail: So I have grouped the following formalisms into a power hierarchy (and made classes for them): Class 1 DFA NFA NFAϵ reg.exp Class 2 (DCFL expressivity?) LR(1) DPDA Class 3 CFG PDA Class 4 TM NTM Class 4 is Read More …

Problem Detail: In a recent CACM article [1], the authors present a way to improve scalability of shared and coherent caches. The core ingredient is assuming the caches are inclusive, that is higher-level caches (e.g. L3, one global cache) contain all Read More …

Problem Detail: Could some one please explain how to get the time complexity of checking if a number is prime? I’m really confused as to if it is $O(sqrt{n})$ or $O(n^2)$. I iterate from $i=2$ to $sqrt{n}$ and continuously checking if Read More …

Problem Detail: I wrote $qquad displaystyle sumlimits_{i=1}^n frac{1}{i} = sumlimits_{i=1}^n cal{O}(1) = cal{O}(n)$ but my friend says this is wrong. From the TCS cheat sheet I know that the sum is also called $H_n$ which has logarithmic growth in $n$. So Read More …

Problem Detail: I know that the CIRCUIT VALUE problem is P-complete. In the CIRCUIT VALUE problem the input is a Boolean circuit together with an input to this circuit, and the answer is the evaluation of the given circuit on the Read More …