Time complexity of the solution to TextJustification seems to be O(n)?

[DaiYue]

I'm wondering that the time complexity of this solution is O(n) rather than O(n^2) ? Seems that each letter is visited and output for just once.

Also I'm curious why the 2 functions _buildLine and _buildSpecialLine has a "_" prefix? Is it because they are private methods and this is some kind of a coding convention? Thanks a lot:)

[soapyigu]

You are right, i guess it is O(n). And the underline prefix is to follow my old java style from my earlier job - all private methods should be named with underline as prefix. I will fix it later, thank you.