// Trees (Group A) are implemented here.
// Graph/Tree Traversal (Group A) is implemented here.
// Complex user-defined algorithm (Group A) is implemented here.
/// <summary>
/// Returns the the Minimum Spanning Tree of the graph, in the form of adjacency list, using Kruskal's algorithm.
/// </summary>
public AdjacencyList Kruskal_GetTree_List()
{
if (!CheckUndirectedGraph())
{
MessageBox.Show("Error in finding the Minimum Spanning Tree: \nThe graph is not undirected!");
return(null);
}
else
{
AdjacencyList outputMST = new AdjacencyList();
int count = 0;
InitialiseEdges();
InitialiseUnionFind();
QuickSort(edges, 0, edges.Count - 1);
while (count < Count() - 1)
{
if (Find(edges[0].vStart).GetLeader() != Find(edges[0].vFinish).GetLeader())
{
count++;
outputMST.SetUndirectedEdge(edges[0].vStart, edges[0].vFinish, edges[0].weight);
Union(Find(edges[0].vStart).GetLeader(), Find(edges[0].vFinish).GetLeader());
}
edges.RemoveAt(0);
}
return(outputMST);
}
}
private void ButtonSubmit_Click(object sender, EventArgs e)
{
bool flag = true;
mapMatrix = new AdjacencyMatrix();
mapList = new AdjacencyList();
for (int col = 1; col <= 26; col++)
{
for (int row = 0; row < 26; row++)
{
dataGridViewAdjacencyMatrix[col, row].Style = dataGridViewCellStyle_Valid;
try
{
if (dataGridViewAdjacencyMatrix[col, row].Value != null && dataGridViewAdjacencyMatrix[col, row].Value.ToString() != "")
{
dataGridViewAdjacencyMatrix[col, row].Value = dataGridViewAdjacencyMatrix[col, row].Value.ToString().Trim();
if (dataGridViewAdjacencyMatrix[col, row].Value != null &&
Convert.ToDouble(dataGridViewAdjacencyMatrix[col, row].Value.ToString()) > 0) // Valid entry
{
mapMatrix.SetDirectedEdge(col - 1, row, Convert.ToDouble(dataGridViewAdjacencyMatrix[col, row].Value.ToString()));
mapList.SetDirectedEdge(col - 1, row, Convert.ToDouble(dataGridViewAdjacencyMatrix[col, row].Value.ToString()));
}
else if (dataGridViewAdjacencyMatrix[col, row].Value != null &&
Convert.ToDouble(dataGridViewAdjacencyMatrix[col, row].Value.ToString()) < 0) // Negative edge exception
{
dataGridViewAdjacencyMatrix[col, row].Style = dataGridViewCellStyle_Invalid;
string colName = Convert.ToChar('A' + col - 1).ToString();
string rowName = Convert.ToChar('A' + row).ToString();
MessageBox.Show("Negative weight at row: " + rowName + ", column: " + colName + "!");
flag = false;
}
}
}
catch // Invalid weight input
{
dataGridViewAdjacencyMatrix[col, row].Style = dataGridViewCellStyle_Invalid;
string colName = Convert.ToChar('A' + col - 1).ToString();
string rowName = Convert.ToChar('A' + row).ToString();
MessageBox.Show("Invalid input at row: " + rowName + ", column: " + colName + "!");
flag = false;
}
}
}
submitSuccessful = flag;
}
// Trees (Group A) are implemented here.
// Graph/Tree Traversal (Group A) is implemented here.
// Complex user-defined algorithm (Group A) is implemented here.
/// <summary>
/// Returns the the Minimum Spanning Tree of the graph, in the form of adjacency list, using Prim's algorithm.
/// </summary>
/// <param name="vStart">The starting vertex.</param>
public AdjacencyList Prim_GetTree_List(int vStart)
{
if (!CheckUndirectedGraph())
{
MessageBox.Show("Error in finding the Minimum Spanning Tree: \nThe graph is not undirected!");
return(null);
}
else
{
List <int> visitedVertices = new List <int>();
List <int> remainingVertices = new List <int>();
AdjacencyList outputMST = new AdjacencyList();
for (int i = 0; i < this.GetSize(); i++)
{
if (this.IsVertexExisting(i))
{
remainingVertices.Add(i);
}
}
visitedVertices.Add(vStart);
remainingVertices.Remove(vStart);
while (remainingVertices.Any())
{
double min = Double.MaxValue;
int newVStart = -1, newVFinish = -1;
foreach (int i in visitedVertices)
{
foreach (int j in remainingVertices)
{
if (ContainsEdge(i, j) && GetEdge(i, j) < min)
{
min = GetEdge(i, j);
newVStart = i;
newVFinish = j;
}
}
}
visitedVertices.Add(newVFinish);
remainingVertices.Remove(newVFinish);
outputMST.SetUndirectedEdge(newVStart, newVFinish, min);
}
return(outputMST);
}
}
private void ButtonSubmit_Click(object sender, EventArgs e)
{
bool flag = true;
mapMatrix = new AdjacencyMatrix();
mapList = new AdjacencyList();
for (int vertex = 0; vertex < 26; vertex++)
{
if (dataGridViewAdjacencyList[1, vertex].Value != null)
{
string adjacentEdges = dataGridViewAdjacencyList[1, vertex].Value.ToString();
byte[] adjacentEdgesBytes = Encoding.ASCII.GetBytes(adjacentEdges.Replace(" ", string.Empty).Replace(",", "\n"));
MemoryStream adjacentEdgesStream = new MemoryStream(adjacentEdgesBytes);
using (StreamReader reader = new StreamReader(adjacentEdgesStream))
{
try
{
string newValue;
string state = "vertex";
char finishingVertex = '\0';
double weight;
while ((newValue = reader.ReadLine()) != null)
{
if (state == "vertex")
{
finishingVertex = Convert.ToChar(newValue);
if (!(finishingVertex >= 'A' && finishingVertex <= 'Z')) // Invalid vertex name exception
{
dataGridViewAdjacencyList[1, vertex].Style = dataGridViewCellStyle_Invalid;
string vertexName = Convert.ToChar('A' + vertex).ToString();
MessageBox.Show("Invalid input at vertex " + vertexName + "!");
flag = false;
continue;
}
else if (finishingVertex == vertex + 'A') // Self loop exception
{
dataGridViewAdjacencyList[1, vertex].Style = dataGridViewCellStyle_Invalid;
string vertexName = Convert.ToChar('A' + vertex).ToString();
MessageBox.Show("Self loop at vertex " + vertexName + "!");
flag = false;
state = "weight";
}
else // Valid input
{
state = "weight";
}
}
else // if (state == "weight")
{
if (newValue.Length == 1 && Convert.ToChar(newValue) >= 'A' && Convert.ToChar(newValue) <= 'Z') // Weight is omitted - default weight 1
{
if (finishingVertex == vertex + 'A') // Self loop exception
{
dataGridViewAdjacencyList[1, vertex].Style = dataGridViewCellStyle_Invalid;
string vertexName = Convert.ToChar('A' + vertex).ToString();
MessageBox.Show("Self loop at vertex " + vertexName + "!");
flag = false;
}
else // Valid input
{
mapMatrix.SetDirectedEdge(vertex, Convert.ToInt32(finishingVertex - 'A'), 1);
mapList.SetDirectedEdge(vertex, Convert.ToInt32(finishingVertex - 'A'), 1);
finishingVertex = Convert.ToChar(newValue);
}
state = "weight";
}
else // Weight is specified
{
weight = Convert.ToDouble(newValue);
if (weight > 0) // Valid input
{
mapMatrix.SetDirectedEdge(vertex, Convert.ToInt32(finishingVertex - 'A'), weight);
mapList.SetDirectedEdge(vertex, Convert.ToInt32(finishingVertex - 'A'), weight);
}
else if (weight < 0) // Negative edge exception
{
dataGridViewAdjacencyList[1, vertex].Style = dataGridViewCellStyle_Invalid;
string vStart = Convert.ToChar('A' + vertex).ToString();
string vFinish = finishingVertex.ToString();
MessageBox.Show("Negative weight at edge " + vStart + vFinish + "!");
flag = false;
}
finishingVertex = '\0';
state = "vertex";
}
}
}
if (finishingVertex != '\0')
{
mapMatrix.SetDirectedEdge(vertex, Convert.ToInt32(finishingVertex - 'A'), 1);
mapList.SetDirectedEdge(vertex, Convert.ToInt32(finishingVertex - 'A'), 1);
}
}
catch
{
dataGridViewAdjacencyList[1, vertex].Style = dataGridViewCellStyle_Invalid;
string vertexName = Convert.ToChar('A' + vertex).ToString();
MessageBox.Show("Invalid input at vertex " + vertexName + "!");
flag = false;
}
}
}
}
submitSuccessful = flag;
}
/// <summary>
/// Compares this instance with a specified adjacency list.
/// </summary>
/// <param name="matrix">The specified adjacency list that this instantce is to be compared with.</param>
/// <returns>
/// Returns NULL if the two adjaceny lists are identical.
/// If the two adjacency lists are different, return a List<int> containing the indexes of different vertices.
/// </returns>
public List <int> CompareTo(AdjacencyList list)
{
bool isEqual = true;
List <int> differentVertices = new List <int>();
if (list == null)
{
isEqual = false;
for (int v = 0; v < GetSize(); v++)
{
if (this.IsVertexExisting(v))
{
if (!differentVertices.Contains(v))
{
differentVertices.Add(v);
}
}
}
differentVertices.Sort();
return(differentVertices);
}
for (int v = 0; v < GetSize(); v++)
{
if (this.IsVertexExisting(v) != list.IsVertexExisting(v))
{
isEqual = false;
if (!differentVertices.Contains(v))
{
differentVertices.Add(v);
}
}
}
for (int v = 0; v < GetSize(); v++)
{
if (this.list[v].Count() != list.list[v].Count())
{
isEqual = false;
if (!differentVertices.Contains(v))
{
differentVertices.Add(v);
}
}
foreach (AdjacentEdge edge in this.list[v])
{
if (!list.list[v].Contains(edge))
{
isEqual = false;
if (!differentVertices.Contains(v))
{
differentVertices.Add(v);
}
}
}
}
if (isEqual)
{
return(null);
}
else
{
differentVertices.Sort();
return(differentVertices);
}
}