I believe this problem has the wrong assertion for part 2. The space rule seems to be to keep spaces between words unless it is something like North Dakota in which you delete the space between the two words. Missouri New Hampshire seems to be missing a space, as only 3 are present. With three entries to delete there should be four spaces Missourix1x2x3xNew (4 x's or spaces for 3 matches).

There's an error in the second test case. This is what's returned: "Error: Error: A MATLAB string constant is not terminated properly." I assume this is due to there being an accidental new-line character in the input string.

I've cleaned up the second test. There was a bad character in there somewhere, but it's working now and I've rescored all the answers.

I get the infamous "Remove inappropriate content" message when trying to submit a solution to this problem.

This is a bizarre one - test case is dependent on how many spaces are between the state names, which points to a specific solution having to be used rather than a solution that makes sense to the user.

Additionally, I have noticed a stange effect in 19a when I use "join". My solution has too few spaces between "Delaware" and "Hawaii", so I thought I'd just bung another one in there with "join". If I do:

s2 = cell2mat(join(s2," ")), % I get the same number of spaces
s2 = cell2mat(join(s2," ")) % I get too many spaces!

Driving me wild...