Walt wrote:
harder than Chinese Algebra.

You thinking of The Chinese Remainder Theorm?

Conditions still firm from the rain on fresh we had more'n a week ago,
followed by no perceptable freeze/thaw cycling i.e. all freeze, so no
softening from weathering, and no softening from sun due to low sun
angle and cold air, which means conditions we better than anything
else one could be doing...