Problem Detail: Can I always increase the complexity of a problem via polynomial reduction? (in which case ‘reduction‘ is really a misnomer) For example, if I have a classic P problem (say, finding the smallest element in an array, by iterating Read More …
Category: Uncategorized
[Solved]: median filter one after the other
Problem Detail: Operate on an image by performing Median Filtering in a 3×3 window. Operate on the resulting image by performing, again, Median Filtering in a 3×3 window. Can the resulting image be obtained from a single Median filtering? my initial Read More …
[Solved]: Time complexity of Depth First Search
Problem Detail: Please forgive me for asking a novice question, but I’m a beginner at algorithms and complexities, and it’s sometimes hard to understand how the complexity for a specific algorithm has come about. I was reading the DFS algorithm from Read More …
[Solved]: Finding vertices for which there either exists a path to all other vertices or other vertices have a path to them
Problem Detail: Or in other words, find all $v in V$ such that there exists a path $forall w in V$ $v rightarrow w$ or $w rightarrow v$. This is for a directed acyclic graph. I need to find an $O(|E| Read More …
[Solved]: Why is the reduction from Vertex-Cover to Subset-Sum of polynomial time?
Problem Detail: In the standard proof why Subset-Sum is (weakly) NP-complete, one reduces Vertex Cover to Subset-Sum by using suitable numbers with O(m+n) bits (where m is the number of edges and n the number of vertices). But how can we Read More …
[Solved]: Time complexity of 8-queen, by placeing one by one without attack
Problem Detail: I am new to artificial intelligence. I have been trying to analyse the time complexity of 8-queen, by placing one by one without attack. One approach to achieve goal state is to “add a queen to any square in Read More …
[Solved]: Why can’t I run a mac program natively on windows?
Problem Detail: Basically, I believe that if you have something like a .dmg file the OS opens it with a certain program which takes the code behind it and does things to it. So why couldn’t you then take the program Read More …
[Solved]: Why does the state remain unchanged in the small-step operational semantics of a while loop?
Problem Detail: Usually I see that in the structural operational semantics representation for the while loop, the program state don’t change: $(while > B > do >S, sigma) rightarrow (if >B > then >S; (while > B > do >S) > Read More …
[Solved]: How does ‘deforestation’ remove ‘trees’ from a program?
Problem Detail: I think understand how deforestation consumes and produces a list at the same time (from a fold and an unfold function — see this good answer on CodeReview here), but when I compared that with the wikipedia entry on Read More …
[Solved]: What is Simultaneous Multithreading
Problem Detail: I come from an electronics background. I know that there are three types of implementations of multithreading (see Computer Architecture: A Quantitative Approach, 5th Edition): Fine-grain multithreading issues instructions for different threads after every cycle. Coarse-grain multithreading only switches Read More …
