Tobias Reif <tobiasreif / pinkjuice.com> schrieb: > So here#s what I had > def diff other > if self.length >= other.length > longer = self.dup > shorter = other.dup > elsif self.length <= other.length > longer = other.dup > shorter = self.dup > end > shorter.each do |el| > if longer.index(el) > longer.delete_at longer.index(el) > end > end > longer > end This is shorter: diff(other) u = self | other i = self & other u == i ? u : u - i end I don't know which is faster. You should benchmark both if speed does matter. -- Don't worry about people stealing an idea. If it's original, you will have to ram it down their throats. -- Howard Aiken