# Series 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: - 491 - 914 - 142 And the following 4-digit series: - 4914 - 9142 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*. ## Setup There are two different methods of getting set up to run the tests with Objective-C: - Create an Xcode project with a test target which will run the tests. - Use the ruby gem `objc` as a test runner utility. Both are described in more detail here: http://exercism.io/languages/objective-c ### Submitting Exercises When submitting an exercise, make sure your solution file is in the same directory as the test code. The submit command will look something like: ```shell exercism submit /objective-c/sieve/Sieve.m ``` You can find the Exercism workspace by running `exercism debug` and looking for the line beginning with Workspace. ## Source A subset of the Problem 8 at Project Euler [http://projecteuler.net/problem=8](http://projecteuler.net/problem=8) ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.