Topologically Sorting DAGS def naive topsort(G,S=None): if S is None: S=set(G) # Default: All nodes if len(S)==1: return list(S)# Base case, single node # Reduction: Remove a node # Recursion (assumption), n=1 v=S.pop () seq=naive topsort (G,S) min i=0 for i,u in enumerate(seq): if v in G[u]: min i=i+1 seq.insert (min i,v) # After all dependencies return seq Using adjacency sets or dicts to represent a DAG.

Topologically Sorting DAGS def naive topsort(G,S=None): if S is None: S=set(G) # Default: All nodes if len(S)==1: return list(S)# Base case, single node # Reduction: Remove a node # Recursion (assumption), n=1 v=S.pop () seq=naive topsort (G,S) min i=0 for i,u in enumerate(seq): if v in G[u]: min i=i+1 seq.insert (min i,v) # After all dependencies return seq Using adjacency sets or dicts to represent a DAG.

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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