## How to convert a PPM image to grayscale in C++

Convert a colored image to grayscale in C++ using the PPM image type and IfranView.

C++ppmgrayscalemultimedia## Paint adjacent boundaries with distinct colors

Did you know that the minimum number of colors needed for this to work is 4?

adjacencybacktrackingac-3colorsPython## Square each element of a Scala list

There are two practical ways to square each element of a list.

pattern matchingmapScala## Summation with rationals

Using Scala and the powers of Recursion.

functional programmingrecursionScala