What is the depth of the water?
The water is deep.
    src        edge_attr  dst
0     0               of    6
1     1   to the left of   10
2     1               of    6
3     2           flying    6
4     3   to the left of    5
5     3               of    6
6     3   to the left of   10
7     5  to the right of    3
8     5   to the left of   10
9     6           flying    2
10    8               of    6
11    9               of    6
12   10  to the right of    5
13   10               of    6
14   10  to the right of    3
15   10  to the right of    1