The number of subsets in the partition

var s = new DisjointSet[Int]
s.add_all([1,2,3,4,5])
assert s.number_of_subsets == 5
s.union_all([1,4,5])
assert s.number_of_subsets == 3
s.union(4,5)
assert s.number_of_subsets == 3

Property definitions

core $ DisjointSet :: number_of_subsets
	# The number of subsets in the partition
	#
	#     var s = new DisjointSet[Int]
	#     s.add_all([1,2,3,4,5])
	#     assert s.number_of_subsets == 5
	#     s.union_all([1,4,5])
	#     assert s.number_of_subsets == 3
	#     s.union(4,5)
	#     assert s.number_of_subsets == 3
	var number_of_subsets: Int = 0
lib/core/collection/union_find.nit:77,2--86,31