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