"linear order" in descriptive complexity description of class P

46 Views Asked by At

In the presence of linear order, first-order logic with a least fixed point operator gives P, the problems solvable in deterministic polynomial time.

So, what does "linear order" mean here?

1

There are 1 best solutions below

0
On BEST ANSWER

It just means that the (finite) structures under consideration also have a distinguished linear order relation. (Or, alternatively, the languages always have a distinguished binary relation symbol $\leq$ that is always interpreted to be a linear order.)