Preflow-push with excess scaling: Difference between revisions

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'''Algorithmic problem:'''
'''Algorithmic problem:'''
[[Max-flow problems|max-flow problem (standard version)]]
[[Max-Flow Problems|max-flow problem (standard version)]]


'''Type of algorithm:'''
'''Type of algorithm:'''

Revision as of 13:37, 29 October 2014

Abstract view

Algorithmic problem: max-flow problem (standard version)

Type of algorithm: loop.

Invariant: Before and after each iteration:

  1. The current flow is feasible.
  2. There is a nonnegative, integral value [math]\displaystyle{ \Delta }[/math].
  3. The excess of no node exceeds [math]\displaystyle{ \Delta }[/math].

Variant: [math]\displaystyle{ \Delta }[/math] is divided by two (integral division).

Break condition: [math]\displaystyle{ \Delta=0 }[/math].

Induction basis

  1. All steps in the induction basis of the preflow push algorithm.
  2. Set [math]\displaystyle{ \Delta }[/math]