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Problem Detail: Basically, is the following statement true? $A leq_p B$ $rightarrow$ $B leq_p A$ Asked By : robowolverine Answered By : Sasho Nikolov Short answer: No. For one example, take $A$ to be the language $A = {0, 1}^*$, i.e. the language Read More …

Problem Detail: Question: Is there established procedure or theory for generating code that efficiently applies a matrix-vector multiplication, when the matrix is dense and filled with only zeros and ones? Ideally, the optimized code would make systematic use of previously computed Read More …

Problem Detail: I have a number of questions about Paxos which I can’t answer in full confidence from reading the paper (Paxos Made Simple). My questions are loosely based around the following quote: In Paxos, a value is chosen when a Read More …

Problem Detail: I am aware that this seems a very stupid (or too obvious to state) question. However, I am confused at some point. We can show that P $=$ NP if and only if we can design an algorithm that Read More …

Problem Detail: This was interview question. When the input is a infinite sequence of numbers starting from 1, what is the nth digit? e.g.) 123456789101112131415161718192021….. here 28th digit is 1. Asked By : Sungguk Lim Answered By : wvxvw Just to add a Read More …

Problem Detail: In the set cover problem we want to find in the $mathbb{S} subset 2^mathbb{U}$ the subset ${s_i}_{1..k}$, such that $cup s_i = mathbb{U}$ for given $K$, where $k le K$. But how to reduce the set cover problem to Read More …

Problem Detail: A pseudo-polynomial time algorithm is an algorithm that has polynomial running time on input value (magnitude) but exponential running time on input size(number of bits). For example testing whether a number $n$ is prime or not, requires a loop Read More …

Problem Detail:  Calculate the FOLLOW sets for all the non terminals: $S rightarrow bEx mid Db mid b mid F$ $D rightarrow EDc mid Y$ $E rightarrow dED mid dDY$ $Y rightarrow ab mid aDx mid varepsilon$ So I know Read More …