Time-Space Lower Bounds for Directed st-Connectivity on Graph Automata Models

نویسندگان

  • Greg Barnes
  • Jeff Edmonds
چکیده

Directed st-connectivity is the problem of detecting whether there is a path from a distinguished vertex s to a distinguished vertex t in a directed graph. We prove time–space lower bounds of ST = Ω( n 2 log n log(n log n/S) ) and S 1

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Tight Lower Bounds for st-Connectivity on the NNJAG Model

Directed st-connectivity is the problem of deciding whether or not there exists a path from a distinguished node s to a distinguished node t in a directed graph. We prove a time– space lower bound on the probabilistic NNJAG model of Poon [Proc. 34th Annual Symposium on Foundations of Computer Science, Palo Alto, CA, 1993, pp. 218–227]. Let n be the number of nodes in the input graph and S and T...

متن کامل

Space Bounds for Graph Connectivity Problems on Node-named JAGs and Node-ordered JAGs

Two new models, NO-JAG and NN-JAG in order of increasing computation power, are introduced as extensions to the conventional JAG model. A space lower bound of R(log2 n/ loglog 11) is proved for the problem of directed st-connectivity on a probabilistic NN-JAG and a space upper bound of O(1og n ) is proved for the problem of directed st-nonconnectivity on a nondeterministic NO-JAG. It as also sh...

متن کامل

On the Eccentric Connectivity Index of Unicyclic Graphs

In this paper, we obtain the upper and lower bounds on the eccen- tricity connectivity index of unicyclic graphs with perfect matchings. Also we give some lower bounds on the eccentric connectivity index of unicyclic graphs with given matching numbers.

متن کامل

Monotone depth lower bound for st connectivity

In Lecture 2, we saw how communication complexity lower bounds yield lower bounds for circuit depth. In particular, we showed that for any function f , D(KWf ) = depth(f) and D(KW f ) = depth (f), where KWf denotes the Karchmer-Wigderson game on f . Using this, we showed that monotone circuits for matching require Ω(n) depth. In this lecture we will show that circuits solving directed s-t conne...

متن کامل

On the edge-connectivity of C_4-free graphs

Let $G$ be a connected graph of order $n$ and minimum degree $delta(G)$.The edge-connectivity $lambda(G)$ of $G$ is the minimum numberof edges whose removal renders $G$ disconnected. It is well-known that$lambda(G) leq delta(G)$,and if $lambda(G)=delta(G)$, then$G$ is said to be maximally edge-connected. A classical resultby Chartrand gives the sufficient condition $delta(G) geq frac{n-1}{2}$fo...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • SIAM J. Comput.

دوره 27  شماره 

صفحات  -

تاریخ انتشار 1998