Which color is the arrow?
The arrow is red.
    src        edge_attr  dst
0     0   to the left of    1
1     0   to the left of   16
2     0   to the left of   14
3     1  to the right of    0
4     1   to the left of   16
5     2   to the left of    5
6     2   to the left of    4
7     3   to the left of    9
8     3   to the left of   15
9     4   to the left of    7
10    4   to the left of    5
11    4  to the right of    2
12    5   to the left of    9
13    5  to the right of    2
14    5  to the right of    4
15    5   to the left of    7
16    6   to the left of    9
17    6   to the left of   11
18    7   to the left of    9
19    7  to the right of    4
20    7  to the right of    5
21    7   to the left of    8
22    8  to the right of    7
23    9  to the right of    5
24    9  to the right of    3
25    9  to the right of    7
26    9  to the right of    6
27   10               on   14
28   11  to the right of    6
29   12  to the right of   13
30   12  to the right of   14
31   13   to the left of   12
32   14   to the left of   12
33   14  to the right of    0
34   14   to the left of   15
35   15  to the right of   14
36   15  to the right of    3
37   16  to the right of    1
38   16  to the right of    0