Flow Network Definition capacity function: c(u,v)≥0 source s and sink t, so that ∃s⇝v⇝t ∀v∈V. flow: f:V×V→R 0≤f(u,v)≤c(u,v) v∈V∑f(v,u)=v∈V∑f(u,v)∀u∈V−{s,t} f(u,v)=0∀(u,v)∈/E supersource and supersink