1
c LEMON max flow problem
2
p max 7 9
3
n 1 s
4
n 7 t
5
a 1 2 3
6
a 1 3 2
7
a 1 4 1
8
a 2 5 3
9
a 3 5 2
10
a 3 7 5
11
a 3 6 3
12
a 4 6 1
13
a 5 7 2
14
a 6 7 4