flow value: 4
flow: 4 0 2 2 2
first partition:  0 1 2
second partition: 3
edges in the cut: 1-3 (2), 2-3 (2), 
flow value: 1
flow: 1 1 0 0 0 0 0
first partition:  0 1 3 4 5
second partition: 2
edges in the cut: 1-2 (1),