10
11
12
13
14
15
16
17
18
19
20
27
28
33
99
100
101
999
1000
1001
1111
1999
2000
2001
2345
9999
10000
9999999
1000000000
888888888888
123123123123123123
999999999999999999
1000000000000000000
0