What is common to the sky and the rooftop?
The color, both the sky and the rooftop are blue.
    src        edge_attr  dst
0     0  to the right of    2
1     1   to the left of   16
2     1        pulled by    6
3     1  to the right of    5
4     1   to the left of   15
5     1  to the right of   14
6     2   to the left of    0
7     4       covered in   14
8     5               on    4
9     5   to the left of    6
10    5   to the left of    1
11    6          pulling    1
12    6       walking on   14
13    6   to the left of   16
14    6   to the left of   15
15    6      attached to    1
16    6       walking in   14
17    6  to the right of   14
18    6  to the right of    5
19    7  to the right of    9
20    7  to the right of    8
21    7  to the right of   12
22    7  to the right of   10
23    7  to the right of   17
24    7  to the right of   13
25    8  to the right of    9
26    8   on the side of    0
27    8   to the left of    7
28    8   to the left of   10
29    8   to the left of   17
30    9   to the left of    7
31    9   to the left of    8
32    9   to the left of   10
33    9   to the left of   12
34    9   to the left of   17
35   10  to the right of    8
36   10  to the right of    9
37   10   on the side of    0
38   10  to the right of   17
39   10   to the left of    7
40   12  to the right of    9
41   12   to the left of    7
42   12        on top of    0
43   13   to the left of    7
44   13        on top of    0
45   14   to the left of    6
46   14   to the left of    1
47   15  to the right of    6
48   15  to the right of    1
49   16  to the right of    6
50   16  to the right of    1
51   17   on the side of    0
52   17  to the right of    9
53   17   to the left of    7
54   17  to the right of    8
55   17   to the left of   10