// Using Prim's algorithm, build a minimum spanning tree of the graph of Cities.
private void BuildTree()
{
// Select a random City to be the tree's root node.
City root = Program.RandomElement <City>(City.ListOf);
Tree = new CityTree(root);
List <City> onTree = new List <City>();
onTree.Add(root);
List <City> offTree = new List <City>(City.ListOf);
offTree.Remove(root);
// Begin Prim's algorithm.
while (onTree.Count < City.Count)
{
City from = onTree[0];
City to = offTree[0];
foreach (City i in onTree)
{
foreach (City j in offTree)
{
if (i.Edges[j.ID] < from.Edges[to.ID])
{
from = i;
to = j;
}
}
}
Tree.Insert(to, from);
onTree.Add(to);
offTree.Remove(to);
}
}
override public void Reset()
{
Tree = null;
Visited = new bool[City.Count];
Result = new List <City>();
}
