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Questions tagged [ford-fulkerson]

The Ford-Fulkerson algorithm is an algorithm for finding the maximum flow in a flow network. It only works on graphs with integer capacities and has poor performance on graphs with large flows.

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Why are back edges required in the Ford-Fulkerson algorithm?

To find the maximum flow in a graph, why doesn't it suffice to only saturate all augmenting paths with the minimum edge capacity in that path without considering the back edges? I mean, what is the point calling it a back edge if we assume flow from…
piyukr
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Maximum flow - Ford-Fulkerson: Undirected graph

I am trying to solve the maxium flow problem for a graph using Ford–Fulkerson algorithm. The algorithm is only described with a directed graph. What about when the graph is undirected? What I have done to mimic an undirected graph is to use two…
Mads Andersen
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maximum bipartite matching (ford-fulkerson)

I was reading http://www.geeksforgeeks.org/maximum-bipartite-matching/ and http://en.wikipedia.org/wiki/Ford%E2%80%93Fulkerson_algorithm and am having trouble understanding. It seems the example is under the assumptions that each job can only accept…
senjougahara
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Ford Fulkerson from Cormen et al

I am studying the Ford-Fulkerson algorithm from Cormen's "Introduction to algorithms 2nd Edition". It is described in pseudo code for a directed graph G=(V, E) as follows where f is a flow defined on VxV FORD-FULKERSON(G, s, t) for each edge…
Lin A
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Why must back-edges be taken into account in Edmonds-Karp Maximum Flow?

I was trying to implement Edmonds-Karp in C++ for maximum flow, and I wrote it slightly differently: Instead of going through all edges in residual graph, I only went through the edges that are present in the original graph, using the adjacency…
xyz
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Time complexity of the Ford-Fulkerson method in a flow network with unit capacity edges

Will the Ford-Fulkerson algorithm find a maximum flow of a unit-capacity flow network (all edges have unit capacity) with n vertices and m edges in O(mn) time?
Jay Patel
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Increase flow by changing only one edge after Ford-Fulkerson

Suppose that I've run the Ford-Fulkerson algorithm on a graph G = (V,E) and the result is a max-flow fmax, which is associated to a min-cut Xmin. I'm interested in increasing the flow as much as possible by increasing the capacity of any one edge…
Richard Gasol
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Which min-cut does the Ford-Fulkerson algorithm find?

There can be multiple min-cuts in a network. E.g: has four min-cuts and Ford-Fulkerson finds the one "nearer" to s (the source). Can we say the same for all networks? That is, Ford-Fulkerson finds the cut nearest to the source? If true, how do we…
Apratim Bhattacharyya
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Max flow in bipartite graph using Ford Fulkerson to determine values to suffice to sum

I'm trying to figure how I should use the Ford Fulkerson algorithm in this situation The situation is kinda sudoku-like. We have a matrix a which contains integer values. The last column of each row and last row of each column, contains the sum of…
Robinhopok
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Max-Flow - Detect If A Given Edge Is Found In Some Min Cut

Given a network G=(V,E) , a max flow f and an edge e in E , I need to find an efficeint algorithm in order to detect whether there is some min cut which contains e. Another question is if I found out the e is contained in some min-cut, is it…
user975343
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Professor Adam's Kids (determine the maximum-flow)

I need help in understanding how to solve the following problem: Professor Adam has two children who, unfortunately, dislike each other. The problem is so severe that not only do they refuse to walk to school together, but in fact each one refuses…
Jubl
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Update Maximum Flow After Adding an Edge

Consider we have a network flow and using Edmond-Karp algorithm, we already have the maximum flow on the network. Now, if we add an arbitrary edge (with certain capacity) to the network, what is the best way to update the maximum flow? I was…
Nima
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Max flow algorithm running time

I have the following two questions. True or false: We can always find a sequence of flow augmenting s-t paths in the Ford-Fulkerson algorithm such that we reach the maximum flow in a polynomial number of iterations. True or false: We can always…
arkham knight
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Ford-Fulkerson Algorithm & Max Flow Min Cut Theorem

Hi I have trouble in studying Ford-Fulkerson Algorithm with max-flow min-cut Theorem . According to the Theorem, The maximum flow should be same as total weight of edges being cut. However, seeing the video…
Jiseop Han
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Why is the complexity of Edmonds-Karp algorithm lesser than Ford-Fulkerson's?

The ford fulkerson complexity is O(FE), but the edmond karps is O(VE^2). This is based on the premise that every edge can only be critical O(V) number of times, and this applies to all the edge so we have O(VE) number of times possible that an edge…
oldselflearner1959
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