Are the sidewalk and the street made of the same material?
Yes, both the sidewalk and the street are made of concrete.
    src        edge_attr  dst
0     0   to the left of    9
1     1   to the left of    3
2     1  to the right of   17
3     1   to the left of    4
4     3  to the right of   13
5     3  to the right of    1
6     3  to the right of   17
7     4  to the right of    1
8     4  to the right of   17
9     4  to the right of   13
10    7  to the right of   10
11    9   on the side of   16
12    9   on the side of   14
13    9  to the right of    0
14   10               by   16
15   10        on top of   14
16   10   to the left of    7
17   10             near   11
18   10               on   16
19   11               in   16
20   11               by   10
21   11   on the side of   16
22   11          next to   10
23   13   to the left of    4
24   13   to the left of    3
25   13  to the right of   17
26   17   to the left of   13
27   17   to the left of    3
28   17   to the left of    1
29   17   to the left of    4