language-agnostic

问题 There is a comment on the question Can the use of C++11's auto improve performance? that scored many votes and suggests “makes it less likely to unintentionally pessimize” as an answer. I've never noticed this term before. I guess it is somehow the opposite of optimization. Can anyone give a more detailed definition? What does it mean in the context of programming? How would pessimized code look like? 回答1: It's mostly a play on words, a pessimist is the opposite of an optimist. And

问题 I'm trying to create an unusual associative array implementation that is very space-efficient, and I need a sorting algorithm that meets all of the following: Stable (Does not change the relative ordering of elements with equal keys.) In-place or almost in-place (O(log n) stack is fine, but no O(n) space usage or heap allocations. O(n log n) time complexity. Also note that the data structure to be sorted is an array. It's easy to see that there's a basic algorithm that matches any 2 of these

问题 Say I have a set D of multisets: D = { {d, g, o}, {a, e, t, t}, {a, m, t}, } Given a multiset M , like M = {a, a, m, t} I would like an algorithm f to give me all elements of D that are subsets (or more precisely, "submultisets") of M : f = {{a, m, t}} If we do only one such query, scanning over all elements of D (in O(#D) time) is clearly optimal. But if we want to answer many such queries for the same D and different M , we might be able to make it faster by preprocessing D into some

问题 Say I have a set D of multisets: D = { {d, g, o}, {a, e, t, t}, {a, m, t}, } Given a multiset M , like M = {a, a, m, t} I would like an algorithm f to give me all elements of D that are subsets (or more precisely, "submultisets") of M : f = {{a, m, t}} If we do only one such query, scanning over all elements of D (in O(#D) time) is clearly optimal. But if we want to answer many such queries for the same D and different M , we might be able to make it faster by preprocessing D into some

问题 read about Pipeline pattern from here how to implement pipeline pattern in java? is there any open source java project that uses pipeline pattern? 回答1: Not sure if you are looking for a specific task processing component or just pipelining software in general. However, JBoss Netty implements a pipeline pattern for attaching and detaching IO processors. It's really intended for NIO based networking stacks (although it does have a local component). Perhaps this will be helpful. 回答2: Regarding

问题 Well, on my free time, I'm making this small web site. The site will not require to authenticate, only some actions (like leaving a comment) will require to do so. I would expect to have up to 100 (probably less) unique visitors a day. I don't really expect more than 50% to (bother to) register. Right now, I'm thinking of three possible authentication mechanisms (but I'm open to suggestions): OpenID authentication; HTTP Digest or at least HTTP Basic authentication; My own (form based)

问题 Let's say I have a weighted graph with weights on both edges and vertices. How do I find the "cheapest" path from a certain node s to a certain node t? My complexity should be O(n 2 (n+m)). 回答1: One way to solve this would be to convert the graph into a new graph in which only edges are weighted, not vertices. To do this, you can split each node apart into two nodes as follows. For any node v, make two new nodes, v1 and v2. All edges that previously entered node v now enter node v1, and all

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . I'm a programmer for some time now yet I haven't found the right websites which offer me the information I'm interested in. I've

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . I'm a programmer for some time now yet I haven't found the right websites which offer me the information I'm interested in. I've

问题 I am looking for a data structure which keeps the top n elements, similar to this question, but with the added requirement of maintaining sort order. Obviously I could just sort at the end but there might be a more efficient way to do it on the fly. There will only be insertions, never removals, and then an iteration through the top n elements at the end. This question is language agnostic but it will be in C# so an answer that uses native .NET collections is preferable. EDIT: I should