Singly-linked List Segments Properties lseg a(i,j)分i一a,j Iseg aB(i,k)j.Iseg a (i,j)*Iseg B(j,k) lseg a-b(i,k)÷j.Iseg a(i,j)*j→b,k list a i台Iseg a(i,nil)
Singly-linked List Segments
Emptyness Conditions For lists,one can derive a law that shows clearly when a list represents the empty sequence: list a i→(i=nil台a=e). For list segments,however,the situation is more complex.One can derive Iseg a(i,j)→(i=nil→(a=e∧j=nil)) Iseg a(i,j)→(i≠j→a卡e). But these formulas do not say whether a is empty when i =j nil
Emptyness Conditions