Depends on method for finding augmenting path.
Use breadth-first search (Edmonds-Karp Algorithm). Thus, the augmenting path is shortest from s to t.
Theorem 27.9
The total number of augmentations is O(VE), O(E) per augmentation. Thus the algorithm has run time O(VE2).
Preflow-Push method yields O(V2E) (Section 27.4), and Lift-to-Front method yields O(V3) (Section 27.5).