Do you see both trains and cars?
Yes, there are both a train and a car.
    src        edge_attr  dst
0     0   to the left of    9
1     0   to the left of    3
2     1   to the left of    8
3     1  to the right of    3
4     1   to the left of    7
5     1  to the right of    5
6     2               of   12
7     3   to the left of   15
8     3   to the left of    1
9     3  to the right of   11
10    3  to the right of    0
11    4               at   12
12    5  to the right of   10
13    5   to the left of    1
14    5  to the right of   14
15    5  to the right of   13
16    5   to the left of   15
17    7  to the right of   15
18    7  to the right of    1
19    8  to the right of    1
20    8               at   12
21    8  to the right of   15
22    9  to the right of    0
23    9               at   12
24    9  to the right of   11
25    9               in   12
26   10   to the left of    5
27   11   to the left of   14
28   11   to the left of   13
29   11   to the left of    9
30   11   to the left of    3
31   13   to the left of    5
32   13  to the right of   11
33   14   to the left of    5
34   14               of    9
35   14  to the right of   11
36   15   to the left of    8
37   15   to the left of    7
38   15               of    9
39   15  to the right of    3
40   15  to the right of    5