Given a string of digits, output all the contiguous substrings of length n in
that string.
For example, the string "49142" has the following 3-digit series:
And the following 4-digit series:
And if you ask for a 6-digit series from a 5-digit string, you deserve whatever you get.
Note that these series are only required to occupy adjacent positions in the input; the digits need not be numerically consecutive.
You can run all the tests for an exercise by entering
$ gradle test
in your terminal.
A subset of the Problem 8 at Project Euler http://projecteuler.net/problem=8
It's possible to submit an incomplete solution so you can see how others have completed the exercise.