Do the wall and the letter have the same color?
Yes, both the wall and the letter are red.
   src        edge_attr  dst
0    0               on    9
1    2  to the right of    3
2    3   to the left of    4
3    3   to the left of    2
4    3  to the right of    5
5    4  to the right of    3
6    5   to the left of    3
7    7               on    3