aggregation tool wanted

i have a perl script which takes in the form 133.10.0.0 133.11.0.0 155.162.0.0/15 155.164.0.0/14 and tells me that i can aggregate the first two into a /15. unfortunately, the actual data as paths can differ 133.10.0.0 2914 2907 133.11.0.0 2914 2907 2501 155.162.0.0/15 2914 155.164.0.0/14 2914 so, what i would like is a tool which takes something like the latter syntax and tells me what the origin ass could aggregate. i.e. i am specifically not inclined to proxy aggregation at this point. Maybe CIDRadvisor does this, but I have been unable to make it do so. randy