Edmonds-Karp: Difference between revisions

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(Created page with "== General Information == '''Algorithmic problem:''' Max-Flow Problems <br> '''Type of algorithm:''' loop<br> ' == Abstract View == '''Invariant:''' After <math>i \ge...")
 
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'''Variant:'''
'''Variant:'''
# The smallest number of arcs on a flow-aumenting <math>(s,t)</math>-path increases (non-strictly) monotonously.
# The smallest number of arcs on a flow-aumenting <math>(s,t)</math>-path increases (non-strictly) monotonously.
# The number of arcs that belong to some flow-augmenting <math>(s,t)</math>-path
# Whenever that number does ''not'' decrease in an iteration, the size of <math>A_f</math> decreases.


'''Break condition:''' There is no flow-augumenting path.
'''Break condition:''' There is no flow-augumenting path.

Revision as of 19:45, 12 October 2014

General Information

Algorithmic problem: Max-Flow Problems

Type of algorithm: loop
'

Abstract View

Invariant: After [math]\displaystyle{ i \ge 0 }[/math] iterations:

  1. The flow [math]\displaystyle{ f }[/math] is a fleasible flow.
  2. If all upper bounds are integral, [math]\displaystyle{ f }[/math] is integral as well.

Notation: For an [math]\displaystyle{ (s,t) }[/math]-flow, let [math]\displaystyle{ A_f }[/math] denote the set of all arcs that belong to at least one flow-augmenting [math]\displaystyle{ (s,t) }[/math]-path with smallest number of arcs.

Variant:

  1. The smallest number of arcs on a flow-aumenting [math]\displaystyle{ (s,t) }[/math]-path increases (non-strictly) monotonously.
  2. Whenever that number does not decrease in an iteration, the size of [math]\displaystyle{ A_f }[/math] decreases.

Break condition: There is no flow-augumenting path.