Category: Uncategorized

Problem Detail: Let $Sigma = { sigma_1 , …, sigma_t }$ and let $S$ be a string from $Sigma^*$. Denote: $n=|S|$, that is $S$ has $n$ letters. I’d like to find the shortest prefix $T$ of $S$ such that $S$ is Read More …

Problem Detail: My approach Let L ∈ P $exists$ Turing Machine $M_1$ which decides L. We can easily construct $M_2$ which decides $bar{L}$ $bar{L}$ ∈ CO-NP $implies$ P ⊆ Co-NP I’m not sure whether its a correct way to prove this Read More …

Problem Detail: I read a theorem which states that: If there exists a polynomial time approximation algorithm for solving the Maximum Clique problem (or the Maximum Independent Set problem) for any constant performance ratio r, then NP = P. But I Read More …

Problem Detail: My problem is due to the fact that I am manipulating a set of amounts that span over some intervals of time (start date/end date) and that are rounded to cents. I have to multiply each of them by Read More …

Problem Detail: I have the following question to answer in a MapReduce assignment sheet The Naive Bayes classifier is a widely-used tool for analyzing data. Consider a data set that has $n$ data items, each of which has the same $m+1$ Read More …

Problem Detail: Perhaps a way to better understand the Halting Problem’s importance is to know what would happen or what could be possible if this was solved. What would be the Halting Problem’s implications in today’s technology, mathematics and its practical Read More …

Problem Detail: I read that testing the length of the input string is in DLOGTIME. The question is how can testing the length of the input string be in DLOGTIME? $text{DLOGTIME} = O(log n)$, so what number would be in $n$? Read More …

Problem Detail: Prove that $L_1$ is regular if $L_2$, $L_1L_2$, $L_2L_1$ are regular. These are the things that I would use to start. As $L_1L_2$ is regular, then the homomorphism $h(L_1L_2)$ is regular. Let $h(L_1) = L_2$ and $h(L_2) = L_1$, Read More …

Problem Detail: I’m learning programming in ML (OCaml), and earlier I asked about ML functions of type ‘a -> ‘b. Now I’ve been experimenting a bit with functions of type ‘a list -> ‘b list. There are some obvious simple examples: Read More …

Problem Detail: I’m designing an in-memory object database for a very specific use case. It is single writer, but must support efficient concurrent reads. Reads must be isolated. There is no query language, the database only supports: get object/-s by attribute/set Read More …