10 11
0 1 2
1 2 1
2 4 1
0 3 1
3 4 5
5 6 3
6 9 2
5 7 5
7 8 -4
8 6 1
8 9 2
0 9

Directed Graph
   2    1    1                3          2
 +--->1--->2---+        +---------->6---------->9
 |             v        |           ^           ^
 0             4        5           |1          |
 |             ^        |           |           |
 +--->3--------+        +--->7---- >8-----------+
  1        5              5    -4         2