Click on the left applet to find a max flow and min cut.
(Not on the applet below.)
The pair of numbers associated with an arc indicates flow/capacity.
The left is a residue network associated with the flow above.
Blue nodes are reachable from s. Blue lines indicate a shortest path from
s to each reachable node when each edge has a unit length.
Min-cost flow will be obtained if the length of each edge is set to be a cost.