What color is the bridge above the water?
The bridge is black.
    src        edge_attr  dst
0     0  to the right of    1
1     0  to the right of    7
2     0  to the right of   13
3     1   to the left of    0
4     1   to the left of    5
5     1            above   10
6     5      in front of    9
7     5  to the right of   12
8     5  to the right of    7
9     5  to the right of   10
10    5  to the right of    6
11    5  to the right of    1
12    6   to the left of   11
13    6   to the left of   13
14    6   to the left of   14
15    6   to the left of    5
16    7               on    1
17    7   to the left of    5
18    7         crossing    1
19    7   to the left of    0
20   10   to the left of   11
21   10   to the left of    5
22   11  to the right of   12
23   11  to the right of    6
24   11  to the right of   10
25   11   to the left of   14
26   12   to the left of   11
27   12   to the left of    5
28   12   to the left of   13
29   13  to the right of    6
30   13  to the right of   12
31   13   to the left of    0
32   13               on    1
33   13               of    7
34   14  to the right of    6
35   14  to the right of   11