Problem Detail: I am trying to find the answer to the following question for the Floyd-Warshall algorithm. Suppose Floyd-Warshall algorithm is run on a directed graph G in which every edge’s length is either -1, 0, or 1. Suppose that G Read More …
Author: ignougroup
“At least one” clause in Relational Algebra
Problem Detail: I’m fairly new to the syntax of relational algebra, and I’m having a hard time understanding how I could set a “at least one” clause. Example: I have: a table with books (listing the title, year published and ID), Read More …
How hard is finding the discrete logarithm?
Problem Detail: The discrete logarithm is the same as finding $b$ in $a^b=c bmod N$, given $a$, $c$, and $N$. I wonder what complexity groups (e.g. for classical and quantum computers) this is in, and what approaches (i.e. algorithms) are the Read More …
Using base 80 for compressing files
Problem Detail: I want to compress file size through making my own numbering system which is 80-based number, I do really want to know whether this even possible ? I learnt that Hexadecimal uses symbols like A, B, C, D, E, F to represent 10,11,12,13,14,15 — Read More …
Problem understanding DFA & NFA equivalence in Theory of Computation
Problem Detail: Before asking this question,I had gone through Equivalence of NFA and DFA – proof by construction but my question is a bit different from that. I was reading Michael Sipser’s Introduction to Theory of Computation and I came to Read More …
What is “memory coalescing”?
Problem Detail: I came to know that the graphic processing unit have something called memory coalescing. On reading on it I was not clear on the topic. Is this any way related to Memory Level Parallelism. I have searched in Google Read More …
Visual programming tools, why don’t they work with the AST directly?
Problem Detail: I’ve found several open source visual programing tools like Blockly and friends, and other projects hosted at Github, but could’t find any that work directly with the abstract syntax tree. Why is that? I’m asking because once I discovered Read More …
What makes type inference for dependent types undecidable?
Problem Detail: I have seen it mentioned that dependent type systems are not inferable, but are checkable. I was wondering if there is a simple explanation of why that is so, and whether or not there is there a limit of Read More …
Prove NP-completeness of deciding satisfiability of monotone boolean formula
Problem Detail: I am trying to solve this problem and I am really struggling. A monotone boolean formula is a formula in propositional logic where all the literals are positive. For example, $qquad (x_1 lor x_2) land (x_1 lor x_3) land Read More …
What is the time complexity of calling successor $n$ times during tree traversal?
Problem Detail: According to some sources, the time complexity of finding the successor of a node in a tree is $O(h)$. So, if the tree is well balanced, the height $h=log n$, and the successor function takes time $O(log n)$. Yet, Read More …
