A b-tree having information stored therein is utilized to facilitate
positional access of elements stored in the leaves of the b-tree. The
b-tree is structured such that for each non-leaf level value, a count is
located to its immediate left and a value is located to its immediate
right. These left and right counts indicate the number of leaf level
values located in the leaves of the sub-trees to the immediate left and
right of the value. The left and right counts are used to determine the
path to take when descending the b-tree in search of a specific position.
The counts can also be utilized to determine the total number of values
in the leaf level of the b-tree.