A single sublist: a base chain plus any number of right-hand chains to subtract. Set difference is left-associative — A - B - C = (A - B) - C, modeled by storing B and C in subtract in order.
A - B - C
(A - B) - C
B
C
A single sublist: a base chain plus any number of right-hand chains to subtract. Set difference is left-associative —
A - B - C=(A - B) - C, modeled by storingBandCin subtract in order.