Remove adjacent identical elements in a Ruby Array?
- by Mike Woodhouse
Ruby 1.8.6
I have an array containing numerical values. I want to reduce it such that sequences of the same value are reduced to a single instance of that value.
So I want
a = [1, 1, 1, 2, 2, 3, 3, 3, 3, 2, 2, 2, 3, 3, 3]
to reduce to
[1, 2, 3, 2, 3]
As you can see, Array#uniq won't work in this case.
I have the following, which works:
(a.size - 1).downto(1) { |i| a[i] = nil if a[i - 1] == a[i] }
Can anyone come up with something less ugly?
