Will timestamp when extra credit was done after due date

Usage: ./as4 <filename>

File format:

-arm [joint/]length ... (joint types: pm for prismatic, pn for pin, ba for ball, dp for double pin)

-path a b (where a and b are coefficients defining the surface described by equation z = ax^3 + by^3)

-cir r (where r is the radius of the cross-section of a vertical cylinder centered at the origin)

-ell a b (where a is the radius in the x direction and b is the radius in the y direction)

The resulting path is the intersection of the cubic surface and the volume specified by the cir or ell flags.