Array comparison

Hi

I have a handful of arrays, and I want to see if any of the values in any of the arrays, appear in any of the other arrays, is there a clean way to do this or would it be a case of comparing them one at a time?

Add all the elements of the arrays into a hash and count the times you add each element.

one = [1, 2, 3, ]
two = [2, 3, 4, ]
three = [3, 4, 5, ]

arr = [one, two, three]

ans =
  arr.reduce(Hash.new(0)){
  |acc, e|
  e.each{|e| acc[e] += 1}
  acc
}

p ans