21 1D0U-2D
1 g 0 2 21 1
2 G 1 3 20 2
3 G 2 4 19 3
4 A 3 5 18 4
5 U 4 6 17 5
6 C 5 7 16 6
7 A 6 8 0 7
8 C 7 9 15 8
9 C 8 10 14 9
10 A 9 11 0 10
11 U 10 12 0 11
12 U 11 13 0 12
13 A 12 14 0 13
14 G 13 15 9 14
15 G 14 16 8 15
16 G 15 17 6 16
17 A 16 18 5 17
18 U 17 19 4 18
19 C 18 20 3 19
20 U 19 21 2 20
21 C 20 0 1 21