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Problem Detail: For example, on x86, we have a set of general registers, each named to the function it carries out. We have an Accumulator, which is a storage for a results of different fixed point operations, we have a Base Read More …

Problem Detail: I am studying different approaches for the definition of computation with continuous dynamical systems. I have been trying to find a nice introduction to the theory of “State transition systems” but failed to do so. Does anybody know a Read More …

Problem Detail: I have a set of strings $S$ and I am using the edit-distance (Levenshtein) to measure the distance between all pairs. Is there an algorithm for finding the string $x$ which minimizes the sum of the distances to all Read More …

Problem Detail: I am solving one of the past exams and I am not certain with my solution to one of the exercises. The exercise is asking to give intuitive meaning to modal $mu$-calculus formula: $$ phi = mu Z. langle Read More …

Problem Detail: $$ L = {a^ib^jc^k mid i,j,k > 0 text{ and } i+k>j} $$ I say it’s not regular. Proof by pumping lemma: Find a string $xy^iz$ that is not in $L$ (respecting the constraints). Let $w=x^py^pz^p$. Let $i=2$. $x^p(y^py^p)z^p$ Read More …

Problem Detail: Say, I have some permutation or combination formula like this, $$frac{n!}{(n-r)!r!},$$ and I want to $bmod$ the result with some big prime ($10^9+7$ for example). I already tried with modular operation and multiplicative inverse but failed (I don’t quite Read More …

Problem Detail: In Haskell, the Monads type class has the bind operator, which is represented by the symbol >>= The type of such operator is: (>>=) :: Monad m => m a -> (a -> m b) -> m b Why Read More …

Problem Detail: As I understand it NP requires a solution to be verifiable in polynomial time. Can you provide examples of solvable problems not verifiable in polynomial time ? Asked By : user533933 Answered By : Raphael Given input $x = langle M Read More …

Problem Detail: In an exercise, I am asked to find a context free grammar for language $L = {a^{2^k}, k in mathbb{N}}$. I have been trying to use a “doubling” variable. If $a^{2n} in L, ninmathbb{N}$ then use this variable to Read More …

Problem Detail: Let $A = mathrm{R}$ be the set of all languages that are recursive, $B = mathrm{RE} setminus mathrm{R}$ be the set of all languages that are recursively enumerable but not recursive and $C = overline{mathrm{RE}}$ be the set of Read More …