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Changes between Initial Version and Version 1 of Ticket #244

initial	v1
1	1	The new concept of the min cost flow classes (see #234) makes it easy to provide interface for the min. cost maximum flow problem, too.
2	2
3		~~E.g.~~ there could be a `maxFlow(Node s, Node t)` function, which could be used instead of `supplyMap()` and `stSupply()`. In this case `Preflow::runMinCut()` should be called to determine the max. flow value (instead of `Circualtion`), and the algorithm have to be initialized as if `stSupport()` was called with this flow value. However apart from that nothing have to be changed.
	3	For example, there could be a `maxFlow(Node s, Node t)` function, which could be used instead of `supplyMap()` and `stSupply()`. In this case `Preflow::runMinCut()` should be called to determine the max. flow value (instead of `Circualtion`), and the algorithm have to be initialized as if `stSupport()` was called with this flow value. However apart from that nothing have to be changed.