Problem Detail: Denote $D$ a set of finite sequences of integers. In Papadimitriou’s “Computational Complexity” in theorem 2.5 it is proved that if a RAM program $Pi$ computes a function $phi$ from $D$ to integers in time $f(n)$, then there is Read More …
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[Solved]: Some questions regarding compilers and assemblers
Problem Detail: Lots of basic questions are there in my mind. I need to clear them. Statement 1: A compiler converts a human-readable codes to object codes, and those are converted to a machine code (executable) by linker. Am I right Read More …
[Solved]: What is the difference between “for infinitely many n” and “for all n”?
Problem Detail: I have read some complexity papers in which “for infinitely many input sizes” is used. What is the difference in the computational complexity context between “for infinitely many input sizes” and “for all input sizes”? Asked By : Jose Antonio Read More …
[Solved]: Expected number of random interval flips needed for sorting a random array
Problem Detail: This question is inspired by the Bogo-Sort algorithm and the discussion of whether there are any worse sorting algorithms than Bogosort. Assume that $A$ is an array initialized by a random permutation on the set $I_n={1,2,ldots, n}$. Consider the Read More …
[Solved]: Using the Master theorem on a recurrence with non-constant a
Problem Detail: I am trying to solve the following equation using master’s theorem. $T(n) = 3^n T(frac{n} 3) + O(1)$ Extracting the b and $f(n)$ values makes sense they are $b=3$ and $f(n)=1$. I am not sure what my $a$ value Read More …
[Solved]: Data General MV/8000 virtues of “No mode bit”
Problem Detail: I’m reading Tracy Kidder’s “The Soul of a New Machine” where a team at Data General design a new machine (codenamed “Eagle”, later named MV/8000). It is 32-bit extension of a previous architecture (the 16-bit Eclipse). One of the Read More …
[Solved]: What if the electricity goes off while a file is being renamed?
Problem Detail: Suppose I’m renaming a file and the electricity goes off right in the middle. Naively, it looks like the file could be in some “half-renamed” state. Maybe the name would have half the old name and half the new Read More …
[Solved]: Is this NP-hard: min-weight n-clique in a complete n-partite graph
Problem Detail: I have a complete $n$-partite graph, where each partite set has $n$ vertices (yes it’s also $n$), so the graph has $n^2$ vertices in total. My problem is to find a minimum weight $n$-clique in the graph. I would Read More …
[Solved]: Team construction in tri-partite graph
Problem Detail: The government wants to create a team with one alchemist, one builder, and one computer-scientist. In order to have good cooperation, it is important that the 3 team-members like each other. Therefore, the government gathers $k$ candidates of each Read More …
[Solved]: Reflection on Concurrency
Problem Detail: Reflection is a common mechanism for accessing and changing the structure of a program at run-time, found in many dynamic programming languages such as Smalltalk, Ruby and Python, and in impoverished form in Java and (hence) Scala. Functional languages Read More …