Provides numerous graph theory based Graph Collections

# Graph theory

Graph theory is the study of graphs, which are mathematical structures used to model pairwise relations between objects. A graph in this context is made up of vertices (also called nodes or points) which are connected by edges (also called links or lines).

## Undirected Graph

UndirectedGraph
All edges of the undirected graph are bidirectional

## Directed Graph

DirectedGraph
All edges of the directed graph are directed from one vertex to another

Union of directed graphs and undirected graphs
This means that only edge relationships can be stored and values cannot be stored.

# Multigraph

A multigraph (in contrast to a simple graph) is a graph which is permitted to have multiple edges (also called parallel edges1), that is, edges that have the same end nodes. Thus two vertices may be connected by more than one edge.

The base implementation of this library is part of the multigraph
It allows each key to produce an edge, but does not allow 2 key equal edges
Each key can represent an edge between two nodes that store values
It is like allowing red and blue edges to exist together but not allowing 2 red or 2 blue

## Undirected Value Graph

UndirectedValueGraph
An undirected graph of values can be set

## Directed Value Graph

DirectedValueGraph
An directed graph of values can be set

## Graph

Graph
Union of directed graphs, undirected graphs, directed value graphs, undirected value graphs

API reference

# Example

import 'package:graph_collection/graph.dart';

void main() {
final g = Graph();

// Base
g.has(1);
g.remove(1);

// Undirected Graph

// Directed Graph

// Undirected value Graph
g.set(1, 2, 3, 4);
g.hasEdge(1, 2, 3);
g.get(1, 2, 3);
g.unSet(1, 2, 3);

g.setBy<int>(1, 2, 3);
g.hasEdgeBy<int>(1, 2);
g.getBy<int>(1, 2);
g.unSetBy<int>(1, 2);

// Directed value Graph
g.setTo(1, 2, 3, 4);
g.hasEdgeTo(1, 2, 3);
g.get(1, 2, 3);
g.unSetTo(1, 2, 3);

g.setToBy<int>(1, 2, 3);
g.hasEdgeToBy<int>(1, 2);
g.getBy<int>(1, 2);
g.unSetToBy<int>(1, 2);
}

graph