Wow, I did a bad job of Round 1A. Probably should have gone for exhaustive search points on A and B, but I didn't see good algorithms for either. For C, I immediately came up with a distribution bias... and then couldn't get my classifier accurate enough. :(
cemeyer/code-jam-quals-2014-cem
My Google Code Jam 2014 Quals responses (B is crappy, C and D may solve large inputs)
C