A mini project to generate balanced sequences

A simple utility

> nbackseq n l w1 w2 w3 ...

and output comma-separated sequences of words from the provided set (w1, w2, ...) of length l so that for any entry there is no repetition of words n items back (n includes the item)

e.g.

> nbackseq 2 2 a b

a,b
b,a

> nbackseq 3 12 house face shoe

house,face,shoe,house,face,shoe,house,face,shoe,house,face,shoe
...

The goal will be to implement and test (unit-tests) two solutions for the problem. Initial one will be based on a simple permutation with selection of solutions which satisfy needed criterion. We will make sure that it works correctly, implement some timing of the execution and then go on to optimize it by adopting the eight queen puzzle solution, which was implemented via backtracking depth-first search.

• Yarik will initiate
  • new repository on github
  • README.md and nbackseq script prototype
  • basic tests
• You will fork repository on github, and implement permutation-based solution, commit, and then submit a PR
• Yarik meanwhile will be adding more tests and assessments, so you will need to merge new additions
• You will implement the optimized solution

• verify that all input words unique