See here
Basic inequality:
flow out of vertices on the source part of the cut capacity of the cut | (1) |
Ford-Fulkerson algorithm: algorithm to find maximum flow using residual graph
This is an example of using continuous optimization (maximum flow) to solve a discrete optimization problem (min cut).
For irrational capacities, the FF algo can lead to infinite number of iterations.
Chosing paths optimally
Dinits algorithm