Copyright for implementation, Zachary Mitchell, 2017 This function accepts a number of any length and then outputs the largest 5 digit number from that input. The problem was defined by jhoffner @ https://www.codewars.com/kata/51675d17e0c1bed195000001 - - - - - - - - - - - - - - - - - - In the following 6 digit number: 283910 91 is the greatest sequence of 2 digits. In the following 10 digit number: 1234567890 67890 is the greatest sequence of 5 digits. Complete the solution so that it returns the largest five digit number found within the number given. The number will be passed in as a string of only digits. It should return a five digit integer. The number passed may be as large as 1000 digits. Adapted from ProjectEuler.net