Network flows and shortest paths
نویسنده
چکیده
Let G = (V,E) be a directed graph with two special vertices: a source s and a sink t. Every edge (u, v) has a capacity cap(u, v) ≥ 0. For convenience, we define cap(u, v) = 0 if (u, v) in not an edge. More specifically, we work with a modified set of edges {(u, v) : (u, v) ∈ E or (v, u) ∈ E} with cap(u, v) = 0 if (u, v) 6∈ E. A flow is a real-valued function on edges with three properties: • Skew symmetry: f(u, v) = −f(v, u). If f(u, v) > 0 we say there is a flow from u to v.
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