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Comment by ABu on Does FNP-complete = NP-complete?

@mdxn It's funny that in complexity theory a number is "complicated". What is going on...

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Comment by ABu on Count number of non-contiguous occurrences in string

This is equivalent to $|S|$ stacked loops where each loop starts at the current position of its above loop plus 1, and ends at $|T|$, so I guess $O(|T|^{|S|})$

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Comment by ABu on Minimum number of bits to codify arrays with bounded sums

I haven't really understand yet why the intervals are of length $p(n-km, k-l)$. Why substracting, in particular, $km$ and $l$ and not different amounts?

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Comment by ABu on Algorithm: sorting a set of numbers based on a "score matrix"

@D.W. Edited. I hope it's more clear now.

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Comment by ABu on Regarding CPU ILP: what actually consistitutes "the current...

Thinking on the "IP is the address of the last retired instruction + 1" idea, since a CPU can decode more than one instruction per-cycle because of its multiscalar nature, does it mean that the...

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Comment by ABu on Memory-efficient representation of keys over a huge domain

Yes that's the kind of strategy I'm trying now, but instead of exploiting common prefixes, I'm trying to exploit any subsequence, in the sense that each bucket is identified by a mask and a witness....

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Comment by ABu on Memory-efficient representation of keys over a huge domain

Could you try to add a little explanation about why you need at least $\lg{n\choose k}$ bits? I have tried to figure it that out by checking out your links but I haven't get it.

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Comment by ABu on Succint data structure for storing n numbers using a...

@D.W. It's counted in the second word of each bucket. The two words payload per bucket contains all the required meta info of the bucket.

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LL grammars and left-recursiviity

Why LL(k) and LL(∞) are incompatible with left-recursion? I understand that a LL(k) language can support left-recursivity provided that with k-overahead tokens can be resolved any ambiguity. But, with...

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Maximum space consumption of stack and queue for DFS and BFS

I'm trying to determine the maximum memory consumption of the "pending nodes" data structure (stack/queue) for both travelings: BFS and (preorder) DFS.Since BFS and DFS while traveling graphs have node...

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Finding a boolean submatrix isomorphic to a specific fixed set of other...

Given a matrix $M$ of certain size $h\times w$, where $h\leq w$, for example $5\times 6$, are also given the following set $B$ of additional all-ones matrices, that I like to call target...

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Is this data structure a hypertree or they are just isomorphic trees?

I have a data structure described as following:- It's a collection of trees.- Each tree has the same structure.- Each tree has information of diferent nature.A example of this data structure: 4 - - - -...

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Connected but not adjacent vertex

Are there specific terms or adjectives in graph theory to name these two situations?Two vertices are non-adjacent (disjoint? I have seen that the term "disjoint" is rather used for paths with...

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Given a row sum vector and a column sum vector, determine if they can form a...

For example, for a boolean matrix of size $3x4$, the column sum vector $C = (3, 3, 0, 0)$ and the row sum vector $R = (2, 2, 2)$ form a match because I can construct the boolean...

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Answer by ABu for Given a row sum vector and a column sum vector, determine...

Based on the, apparently famous paper on the field, Ryser 56, and the thesis recommended by @orlp, the test to know if a row and column sum vectors forms a match, e.g., a matrix $M_{h,w}$ exists having...

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Polynomial-time algorithm to solve the maximum vertex bipartite subgraph problem

I'm trying to find an algorithm that solves the maximum vertex biclique problem. I know that that algorithm can be solved in polynomial time (in contrast with the maximum edge biclique problem, which...

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Parall execution of algorithms that solves polynomically disjoint subsets...

I was thinking in the following approach for solving a problem that is believe to be a NP-hard problems today in polynomial time, assuming the following:There exists a believed-today NP-hard problem...

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Floating-point oblivious way to compute multiset numbers

I have to compute $R = \left(\!\!{n + 1\choose k}\!\!\right)$, which happens to be:$$R = \left(\!\!{n+1\choose k }\!\!\right) = \binom{n+k}{k} = \frac{(n + k)!}{n!k!} =...

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Number of maximal cliques in graphs without common neighbourhoods

Let's consider a graph $G(n)$ of $n$ vertices such as no two vertices in $G$ have the same exact neighbors (different open neighbourhoods to be more specific; I wonder if this kind of graphs have...

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This costs minimization problem, is it solvable in polynomial time?

I have the following problem: I have $c$ conflicts, named $(c_1, \ldots, c_c)$, where each conflict $c_i$ has certain size $s_i\in\mathbb{N}_0$: the number of times conflict $c_i$ has happened. Also, I...

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A multidimensional "moving van problem": a mix of a knapsack and a...

This problem is a mix of the bin-packing and the knapsack problems. I call it "the moving van problem": there is a moving van with a limit on the weight it can transport, and a set of boxes that you...

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Answer by ABu for Find maximal clique consisting of at least half of the...

Each time you remove a vertex $v$ with degree $<c−1$, the degree of all its neighbours will be reduced by 1, so if any neighbor $u$ gets a degree $<c−1$ after removing $v$, remove $u$ as well;...

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Answer by ABu for Does any language need to have a bottom type?

In actual programming languages, a function is not forced to deal explicity with input is not meant to. For a function f(x) you can say something like:// x must satisfy x != 0, otherwise inv(x) results...

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Average branching factor of an undirected graph

I'm trying to determine, given an unweighted undirected graph, the maximum number of leaves of any travelling of the graph, which means, the maximum number of leaves among all traversals of every...

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Transforming a multidimensional 0-1 knapsack problem to a maximum weighted...

Just out of theoretical curiosity, is there a way to transform a 0-1 multimensional knapsack problem to a maximum clique problem? Or maybe even easier, to a maximum weighted clique problem (the weights...

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Answer by ABu for Algorithm for solving a mixed integer programming problem...

Since the value of each $m_i$ doesn't matter (you can assign $m_i=\lfloor a_ik\rfloor$ as far as the $[b_ik-1, a_ik]$ contains an integer), your problem can be re-formulated...

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Minimum number of bits to codify arrays with bounded sums

I have a very big set of non-empty arrays of possibly repeated numbers sorted in a weakly-decreasing order where each number belongs to the interval $[1, 55]$ and the sum of the elements of each array...

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Regarding CPU ILP: what actually consistitutes "the current instruction"?

If a CPU is able to execute multiple instructions in parallel, and fetching/decoding/scheduling instructions happen in batches, and there's multiple execution units, etc. What does the IP register...

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Memory-efficient representation of keys over a huge domain

I don't know if the title of the question is accurated or not, but I was thinking of the following problem:I have a set of numbers, let's call them identifiers. Each identifier is stored on a 64-bit...

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