Is there a way to detect in an array of say 1…500, if some of the
numbers may be missing from the set.
If you have an array of 1 to 500 called ‘a’ and you wanted to know if
any were missing you could do:
a.uniq.size and if that doesn’t equal 500 you are missing some.
If you need to know which ones are missing you could create a new
array of 1 to 500 and subtract the original
b = (1…500).to_a
b - a