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you are given a flow network g(v, e) with source s and sink t, and whose edgesallhaveacapacityofone,thatis,ce

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User Mattis
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Answer: As given, we have a flow network G(V,E) with source s and sink t, and all edges have a capacity of one, that is, ce=1 for all e∈E.

To find the maximum number of edge-disjoint paths from s to t in G, we can use the Ford-Fulkerson algorithm, which works as follows:

Start with an empty flow f(e) = 0 for all e ∈ E.

While there exists an augmenting path from s to t in the residual graph Gf:

a. Find an augmenting path p in Gf from s to t.

b. Compute the bottleneck capacity b of path p.

c. Update the flow along path p by adding b to each forward edge and subtracting b from each backward edge.

The maximum flow from s to t is equal to the sum of flow along all edges leaving s in the final residual graph Gf.

To find the maximum number of edge-disjoint paths, we can repeatedly run the Ford-Fulkerson algorithm on G, while removing the edges that are used in the paths found so far. We can stop when we are unable to find any more paths from s to t in the residual graph.

Each path found by the Ford-Fulkerson algorithm corresponds to a single edge-disjoint path from s to t in the original graph G, as the flow along each edge is either 0 or 1. Therefore, the maximum number of edge-disjoint paths from s to t in G is equal to the maximum flow from s to t in G.

Since all edges in G have a capacity of 1, the maximum flow from s to t in G will be equal to the maximum number of edge-disjoint paths from s to t. We can use the Ford-Fulkerson algorithm to compute this value.

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User Pfirpfel
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