A Sophie Germain Prime is a prime number P such that 2P+1 is prime as well. Given a prime number as input, your task is to determine whether it is a Sophie Germain Prime.
Standard Input/Output rules and Default Loopholes apply.
This is a decision-problem, so standard rules for this tag apply (re...
100 Rep for a sub-exponential time tweetable integer factorizer
Let n denote the length of the input integer.
Write a valid answer to that challenge that implements a factorization algorithm that runs in worst-case sub-exponential time in n.
For example Pollard-Rho runs in exponential time with...
Given a Prüfer code generate its tree
This is the dual of this challenge, now you're given a Prüfer code/Prüfer sequence and the task is to generate its corresponding tree.
A Prüfer sequence of length n-2 is a unique encoding of a tree with n nodes, its origin lies in a proof of the fact that t...
Is it a Chen prime?
A number is a Chen prime if it satisfies two conditions:
It is prime itself
Itself plus two is either a prime or a semi-prime.
A prime is a number where it has exactly two divisors and those divisors consist of itself and one.
A semi-prime is a number which has exactly t...
I have huge Python modules(+8000 lines) .They basically have tons of functions for interacting with a hardware platform via serial port by reading and writing to hardware registers.
They are not numerical algorithms. So application is just reading/writing to hardware registers/memory. I use thes...
House of cards (version 2)
See version 1. Thanks to FryAmTheEggman for the idea for this second version.
Not-so-simple challenge: given a number of cards, build the tallest house you can with that number of cards. Examples:
Input: 2
Output:
/\
Input: 3
Output:
/\
Input: 5
Output:
--
/\/\...
Let's face it: our Fibonacci challenge is not great.
To quote a recent effort of mine to improve on the situation:
...the challenge is old and outdated; is severely under-specified; allows for two types of solutions; has answers that don't have easy ways to try online; and in general, is lac...
I've seen some posts about merged questions on Meta Stack Overflow. What are merged questions, who can merge questions and what is the policy around this? What happens to reputation on questions and answers for merged questions? Is this similar to closing? Can users vote to merge and unmerge or i...
You must evaluate a string written in Reverse Polish notation and output the result.
The program must accept an input and return the output. For programming languages that do not have functions to receive input/output, you can assume functions like readLine/print.
You are not allowed to use any...
