Which kind of vehicle are the buildings behind of?
The buildings are behind the car.
    src        edge_attr  dst
0     0  to the right of    1
1     0   to the left of   15
2     1  to the right of    9
3     1   to the left of   14
4     1   to the left of    5
5     1   to the left of    4
6     1   to the left of    2
7     1   to the left of    0
8     2  to the right of    1
9     2   to the left of    8
10    2  to the right of   12
11    2   to the left of    4
12    3           behind   10
13    4   to the left of    8
14    4  to the right of   12
15    4  to the right of    2
16    4  to the right of    1
17    4  to the right of    5
18    5  to the right of   12
19    5   to the left of    8
20    5  to the right of    1
21    5   to the left of    4
22    6               on    7
23    6      in front of   10
24    6             near   10
25    6  to the right of   10
26    6   to the left of    8
27    6   to the left of   15
28    6  to the right of   11
29    8  to the right of    2
30    8  to the right of    6
31    8  to the right of    5
32    8  to the right of    4
33    9  to the right of   10
34    9   to the left of    1
35   10   to the left of    9
36   10   to the left of    6
37   10      in front of    3
38   10           behind    6
39   10             near    6
40   11   to the left of   12
41   11   to the left of    6
42   12   to the left of    2
43   12  to the right of   11
44   12   to the left of    5
45   12   to the left of    4
46   14   to the left of   15
47   14  to the right of    1
48   15           beside    6
49   15  to the right of    6
50   15  to the right of   14
51   15  to the right of    0