Consider a directed acyclic graph G E). We run DFS on G from a E V. This results in a BFS forest with two trees T1 = (V1, E1) and T = (V2, E2), where a € V1. Prove or disprove the following statements. a There must exist a topological sort O of G in which every v e V½ occurs before every w e Vị.

Consider a directed acyclic graph G E). We run DFS on G from a E V. This results in a BFS forest with two trees T1 = (V1, E1) and T = (V2, E2), where a € V1. Prove or disprove the following statements. a There must exist a topological sort O of G in which every v e V½ occurs before every w e Vị.

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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