Question: PROBLEM 3 (35 points). In a particular network G (V, E) whose edges have integer capacities Ce, we have already found the maximum flow f

 PROBLEM 3 (35 points). In a particular network G (V, E)

PROBLEM 3 (35 points). In a particular network G (V, E) whose edges have integer capacities Ce, we have already found the maximum flow f from node s to node t. However, we now find out that one of the capacity values we used was wrong: for edge (u,v) we used Cuv whereas it should have been Cuv 1. This is unfortunate because the flow f uses that particular edge at full capacity: fuu = Cuv. We could redo the flow computation from scratch, but there's a faster way. Show how a new optimal flow can be computed in O(IV+ |ED) time. Precisely, construct an algorithm that given the following input, produces the following output. Input - A flow network G = (V, E) with capacities Ce> 0 for each e e E, a precomputed maximum s-t flow f, and an edge (u, v) whose capacity is incorrect. Output - A new maximum flow f' using capacities Cuv = Cuv - 1 and ce = ce for all e # (u, v). Prove that your algorithm is correct and runs in O(V[+ |El) time. Hint: it may be helpful to consider the set of vertices reachable from u in the residual graph

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