I am trying to create a matrix NxN with a MapReduce routine.
To do so I need to iterate on a list of values and compare all the
items of the list with each other.
The problem is that in the reduce method only an Iterable<Writable> is
given and with such object you cannot compute all the possible pairs
because I need 2 indexes.
Moreover the Iterable is not clonable.
How can I solve this problem? Is there any standard technique to use?