A difference pyramid is a pyramid where each new diagonal is the absolute value of the differences between the elements of the last diagonal. For example, if we start with the array
2 5 4 9 3 4
Now, we arrange these in a diagonal column:
2
5
4
9
3
...
A binary recurrence sequence is a recursively-defined sequence of the following form:
This is a generalization of the Fibonacci (x = 1, y = 2, a = [1, 1], alpha = 1, beta = 1) sequence and the Lucas (x = 1, y = 2, a = [2, 1], alpha = 1, beta = 1) sequence.
The Challenge
Given n, x, y, a, alp...
Recent progress
March 2014: Good news! Python 3.4 ships with Pip. Pip has long been Python's de-facto standard package manager. You can install a package like this:
pip install httpie
Wahey! This is the best feature of any Python release. It makes the community's wealth of libraries accessibl...
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Convex, 9 bytes
New method! Also, I realized that is it pretty much exactly the same as Luis' answer but in Convex, but I came up with this independently.
'{,®\W"Oò
Try it online!
Explanation:
'{, Array of chars from NUL to 'z
®\W" Regex to match non-word characters
...
In this challenge, given a list of ghosts from Pac-Man, you must output which ghosts are missing. You must do it in as few bytes as you can
Input
Input will consist of a string, which will be a list of ghosts, which are;
Blinky
Inky
Pinky
Clyde
However, the list may also include Pac-Man (wi...
