fix list index out of range error (#2122)

Nixon

2024-10-09 5dbe6898cac191d12c487772d7336ab2b2a9c350

1
2
3
4
5
6
7
8
9
c    1
cc    2
ccc    3
cd    4
d    5
dc    6
dcc    7
dccc    8
cm    9