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