Problem Detail: I understand the basics of how left-recursion works, and why some people say it’s bad. And I’ve also ready opinions such as: …like LL and LR parsing, PEGs are often frustrating to use in practise. This is, principally, because Read More …
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[Solved]: Checking whether a number divides any of a set of other numbers
Problem Detail: Consider a static set $S$ of positive numbers from range $[1..10^9]$. Is there an efficient algorithm to answer queries of the form: “Given a number $d$ is there an element $x in S$ such that $d | x$”. Simple Read More …
[Solved]: Longest “bounded” subsequence
Problem Detail: Given a sequence of comparable objects $a_1, a_2, ldots a_n,$ how quickly can we find the longest subsequence $s$ such that $s_i > s_1$ for $i > 1$? Or equivalently, how quickly can we find $$ underset{i}{argmax} ; # Read More …
[Solved]: How do you determine the inputs to a neural network?
Problem Detail: I’m looking at this tutorial on neural networks. The data that is given from the UCI study includes various attributes, such as “mean x of on pixels”, “total # on pixels” etc, which are taken as input to the Read More …
[Solved]: What was going on before PAC learning
Problem Detail: I am investigating PAC learning (computational learning theory) as a beginner with no previous knowledge of machine learning / AI. I am investigating the model mainly from a historical point of view. For this, the most important things are Read More …
[Solved]: Unification — most specific unifier
Problem Detail: In unification, given a set of equations, a standard problem is to compute a most general unifier (mgu). I am interested in a somewhat reversed problem. Imagine having a set of equations that do not have an mgu, like Read More …
[Solved]: Complexity of the decision version of determining a min-cut
Problem Detail: I was wondering what the complexity of the following problem is: Given: A flow network $N$ with a source $s$, sink $t$ and a number $k$. Question: Is there an $s$-$t$ cut of capacity at most $k$? Obviously, the Read More …
[Solved]: Small-step semantics: for-loops
Problem Detail: I’m trying to construct the small-step semantic rules involving the for-loops, but I can’t find anything about it in the literature (only about while-loops). I was wondering if anyone could help me out with this? This is a first Read More …
[Solved]: what is the difference between memory access and data memory access?
Problem Detail: what is the difference between memory access and data memory access? for example, here are the examples of register transfer language instructions: $R1 ←[18]$ $R2 ←[R1 +3]$ $R1 ← R1 +2$ $[8] ← R1$ From my understanding, memory access Read More …
[Solved]: Direction of restriction for NP hard proves
Problem Detail: I have a very silly question, as I am reading through all the proofs showing a problem is NP hard, one of the techniques is by showing an already-proven NP complete problem is a special case for that problem. Read More …