$Checking two ordered doubly linked list are equal is O(n) time and [math]O(1)[/math] space. You simply check the head discarding them in order.$

$Checking two unordered doubly linked list are equal is O(n) time and [math]O(n)[/math] space. You place the elements of one list in a hashtable and use that to check with the other list.$

Podeu fer drecera sobre la desigualtat, però no beneficia el pitjor dels casos.

El mateix passa per a una llista individual enllaçada, per la qual cosa estar doblement enllaçat és una arengada vermella.