What's the floor made of?
The floor is made of concrete.
    src        edge_attr  dst
0     0  to the right of   11
1     1   to the left of   10
2     1   to the left of    8
3     2  to the right of   11
4     2   to the left of    4
5     2  to the right of   15
6     3   to the left of   12
7     3   to the left of   10
8     3   to the left of    9
9     3   to the left of    7
10    3   to the left of    6
11    3   to the left of   15
12    3   to the left of   14
13    4  to the right of    2
14    4  to the right of   11
15    5   to the left of   12
16    5   to the left of   14
17    6   to the left of   12
18    6   to the left of   11
19    6   to the left of   14
20    6  to the right of    3
21    6   to the left of   15
22    7  to the right of    3
23    8   to the left of   10
24    8  to the right of    1
25    9   to the left of   11
26    9  to the right of    3
27   10   to the left of   11
28   10  to the right of    8
29   10  to the right of    1
30   10  to the right of    3
31   11  to the right of   10
32   11  to the right of   15
33   11  to the right of   14
34   11   to the left of   13
35   11   to the left of    2
36   11  to the right of    6
37   11  to the right of    9
38   11   to the left of    0
39   11   to the left of    4
40   12  to the right of    5
41   12  to the right of    6
42   12  to the right of    3
43   13  to the right of   11
44   14  to the right of    3
45   14  to the right of    5
46   14   to the left of   11
47   14  to the right of    6
48   15  to the right of    6
49   15  to the right of    3
50   15   to the left of   11
51   15   to the left of    2