Consider the following directed graph G. The numbers next to each edge denote the cost of the edge. (There are arrows; they're just tiny.) 2 4 2 3 2 (a) Run Dijsktra's algorithm to find d(s, v) (the shortest distance from s to v) for all vertices v. (b) Change the cost of edge (b, a) to –2. What is the shortest distance from s to a now? (You can answer this by inspecting the graph.) Run Dijkstra's algorithm until it creates an error, and explain what went wrong (and why).

Consider the following directed graph G. The numbers next to each edge denote the cost of the edge. (There are arrows; they're just tiny.) 2 4 2 3 2 (a) Run Dijsktra's algorithm to find d(s, v) (the shortest distance from s to v) for all vertices v. (b) Change the cost of edge (b, a) to –2. What is the shortest distance from s to a now? (You can answer this by inspecting the graph.) Run Dijkstra's algorithm until it creates an error, and explain what went wrong (and why).

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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