B-tree: find: Difference between revisions

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== Induction Basis ==
== Induction Basis ==
'''Abstract view:''' '''''p''''' is initialized so as to point to the root of the B-tree.
'''Implementation:''' Obvious.
'''Proof:''' Obvious.


== Induction Step ==
== Induction Step ==


== Complexity ==
== Complexity ==

Revision as of 22:03, 25 September 2014

General Information

Algorithmic problem: Sorted sequence: find

Type of algorithm: loop

Auxiliary data: A pointer p of type "pointer to a B-tree node".

Abstract View

Invariant: Before and after each iteration:

  1. p points to some node N of the B-tree and
  2. the searched key is in the range of N.

Variant: p is redirected from the current node N to some child of the current node.

Break condition:

  1. p points to a leaf of the B-tree or (that is, inclusive-or)
  2. the searched key is in the node to which p points.

Induction Basis

Abstract view: p is initialized so as to point to the root of the B-tree.

Implementation: Obvious.

Proof: Obvious.

Induction Step

Complexity