Updated README.md

Source/Framework/Algorithms/EdgeWeightedDigraph.cs

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+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Framework.Collections
+{
+    /// <summary>
+    /// The EdgeWeightedDigrpah class represents an edge-weighted directed graph of vertices named 0 through V-1, where each directed edge
+    /// is of type DirectedEdge and has real-valued weight.
+    /// </summary>
+    /// <seealso href="http://algs4.cs.princeton.edu/44sp/EdgeWeightedDigraph.java.html">EdgeWeightedDigraph class from Princeton University's Java Algorithms</seealso>
+    public class EdgeWeightedDigraph
+    {
+        private readonly LinkedList<DirectedEdge>[] _adjacent;
+        /// <summary>
+        /// Constructs an empty edge-weighted digraph with the specified number of vertices and 0 edges
+        /// </summary>
+        /// <param name="vertices">Number of vertices in the Graph</param>
+        public EdgeWeightedDigraph(int vertices)
+        {
+            NumberOfVertices = vertices;
+            NumberOfEdges = 0;
+            _adjacent = new LinkedList<DirectedEdge>[NumberOfVertices];
+            for (int v = 0; v < NumberOfVertices; v++)
+            {
+                _adjacent[v] = new LinkedList<DirectedEdge>();
+            }
+        }
+        /// <summary>
+        /// The number of vertices in the edge-weighted digraph
+        /// </summary>
+        public int NumberOfVertices { get; private set; }
+        /// <summary>
+        /// The number of edges in the edge-weighted digraph
+        /// </summary>
+        public int NumberOfEdges { get; private set; }
+        /// <summary>
+        /// Adds the specified directed edge to the edge-weighted digraph
+        /// </summary>
+        /// <param name="edge">The DirectedEdge to add</param>
+        /// <exception cref="ArgumentNullException">DirectedEdge cannot be null</exception>
+        public void AddEdge(DirectedEdge edge)
+        {
+            if (edge == null)
+            {
+                throw new ArgumentNullException("edge", "DirectedEdge cannot be null");
+            }
+
+            _adjacent[edge.From].AddLast(edge);
+        }
+        /// <summary>
+        /// Returns an IEnumerable of the DirectedEdges incident from the specified vertex
+        /// </summary>
+        /// <param name="vertex">The vertex to find incident DirectedEdges from</param>
+        /// <returns>IEnumerable of the DirectedEdges incident from the specified vertex</returns>
+        public IEnumerable<DirectedEdge> Adjacent(int vertex)
+        {
+            return _adjacent[vertex];
+        }
+        /// <summary>
+        /// Returns an IEnumerable of all directed edges in the edge-weighted digraph
+        /// </summary>
+        /// <returns>IEnumerable of of all directed edges in the edge-weighted digraph</returns>
+        public IEnumerable<DirectedEdge> Edges()
+        {
+            for (int v = 0; v < NumberOfVertices; v++)
+            {
+                foreach (DirectedEdge edge in _adjacent[v])
+                {
+                    yield return edge;
+                }
+            }
+        }
+        /// <summary>
+        /// Returns the number of directed edges incident from the specified vertex
+        /// This is known as the outdegree of the vertex
+        /// </summary>
+        /// <param name="vertex">The vertex to find find the outdegree of</param>
+        /// <returns>The number of directed edges incident from the specified vertex</returns>
+        public int OutDegree(int vertex)
+        {
+            return _adjacent[vertex].Count;
+        }
+        /// <summary>
+        /// Returns a string that represents the current edge-weighted digraph
+        /// </summary>
+        /// <returns>
+        /// A string that represents the current edge-weighted digraph
+        /// </returns>
+        public override string ToString()
+        {
+            var formattedString = new StringBuilder();
+            formattedString.AppendFormat("{0} vertices, {1} edges {2}", NumberOfVertices, NumberOfEdges, Environment.NewLine);
+            for (int v = 0; v < NumberOfVertices; v++)
+            {
+                formattedString.AppendFormat("{0}: ", v);
+                foreach (DirectedEdge edge in _adjacent[v])
+                {
+                    formattedString.AppendFormat("{0} ", edge.To);
+                }
+                formattedString.AppendLine();
+            }
+            return formattedString.ToString();
+        }
+    }
+
+    /// <summary>
+    /// The DirectedEdge class represents a weighted edge in an edge-weighted directed graph. 
+    /// </summary>
+    /// <seealso href="http://algs4.cs.princeton.edu/44sp/DirectedEdge.java.html">DirectedEdge class from Princeton University's Java Algorithms</seealso>
+    public class DirectedEdge
+    {
+        /// <summary>
+        /// Constructs a directed edge from one specified vertex to another with the given weight
+        /// </summary>
+        /// <param name="from">The start vertex</param>
+        /// <param name="to">The destination vertex</param>
+        /// <param name="weight">The weight of the DirectedEdge</param>
+        public DirectedEdge(uint from, uint to, double weight)
+        {
+            From = from;
+            To = to;
+            Weight = weight;
+        }
+        /// <summary>
+        /// Returns the destination vertex of the DirectedEdge
+        /// </summary>
+        public uint From { get; private set; }
+        /// <summary>
+        /// Returns the start vertex of the DirectedEdge
+        /// </summary>
+        public uint To { get; private set; }
+        /// <summary>
+        /// Returns the weight of the DirectedEdge
+        /// </summary>
+        public double Weight { get; private set; }
+        /// <summary>
+        /// Returns a string that represents the current DirectedEdge
+        /// </summary>
+        /// <returns>
+        /// A string that represents the current DirectedEdge
+        /// </returns>
+        public override string ToString()
+        {
+            return $"From: {From}, To: {To}, Weight: {Weight}";
+        }
+    }
+}