[UVA][循環] 11701 - Cantor
Problem C: Cantor
The ternary expansion of a number is that number written in base 3.
A number can have more than one ternary expansion. A ternary
expansion is indicated with a subscript 3.
For example, 1 = 13 = 0.222...3,
and 0.875 = 0.212121...3.
The Cantor set is...
