Notes on the method

I was given the following challenge:
Write a program that takes as inputs two file paths and uses a metric to determine how similar they are. Documents that are exactly the same should get a score of 1, and documents that don’t have any words in common should get a score of 0.

View my solution code here.

For the solution I avoided libraries or known algorithms and made a brute force answer. I reviewed the main strategy I learned at Hunter College for DNA testing, the Needleman-Wunsch algorithm, mostly because I couldn't quickly figure out how to implement it. So my naive strategy is this:

1. Take the two input strings, remove punctuation, spaces, and any non alpha chars, to create a pair of word arrays
2. Tally any members of List 1 that do not occur in list 2.
3. Repeat the orphan tally but in the reverse direction, tallying any members of List 1 that do not occur in list 2.
4. Return a similiarity score: take the inverse of the average of orphans/allwords. So on a scale of 0 to 1, 1 represents utter disimilarity and 0 represents complete identity.

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