1 0
2 [2, 19]
2 [2, 5]
2 2
3 [2, 19]
3 [2, 5]
3 2
4 [2, 19]
4 [2, 5]
4 2
5 [5, 8]
5 [2, 19]
5 [2, 5]
5 3
6 [5, 8]
6 [2, 19]
6 2
7 [5, 8]
7 [2, 19]
7 2
8 [5, 8]
8 [2, 19]
8 2
9 [2, 19]
9 1
10 [2, 19]
10 [10, 17]
10 2
11 [2, 19]
11 [10, 17]
11 2
12 [2, 19]
12 [10, 17]
12 2
13 [2, 19]
13 [10, 17]
13 2
14 [2, 19]
14 [10, 17]
14 2
15 [2, 19]
15 [10, 17]
15 2
16 [2, 19]
16 [10, 17]
16 2
17 [2, 19]
17 [10, 17]
17 2
18 [2, 19]
18 [18, 20]
18 2
19 [2, 19]
19 [18, 20]
19 2
3