Tree Efficiency
•A tree
is balanced
–if its
balance factor is zero and its subtrees are also balanced
–but,
since this definition occurs so seldom, an alternate definition is more generally
applied:
–a
binary tree is balanced if the height of its subtrees differs by no more than
one (i.e., the balance factors can be -1, 0, or 1) and its subtrees are also
balanced.