public void Swap(ref MinHeapObject a, ref MinHeapObject b)
{
int tempPrio = a.priority;
int tempVertix = a.vertix;
a.priority = b.priority;
a.vertix = b.vertix;
b.priority = tempPrio;
b.vertix = tempVertix;
}
public bool isMember(MinHeapObject m)
{
for (int i = 1; i < _index; i++)
{
if (m.vertix == _collection[i].vertix)
{
return true;
}
}
return false;
}
public void Insert(MinHeapObject a)
{
_collection[_index] = a;
HeapifyUp(_index);
_index++;
}
public MinHeapObject ExtractMinimum()
{
MinHeapObject minimum = new MinHeapObject(_collection[1].priority, _collection[1].vertix);
_collection[1].vertix = _collection[_index - 1].vertix;
_collection[1].priority = _collection[--_index].priority;
_collection[_index] = new MinHeapObject();
Heapify();
return minimum;
}
public void decreasekey(MinHeapObject m)
{
//Console.WriteLine("m.vertix : {0} , m.priority : {1}", m.vertix, m.priority);
for (int i = 1; i < _index; i++)
{
if (m.vertix == _collection[i].vertix)
{
//Console.WriteLine("vertix found");
// Console.ReadLine();
_collection[i].priority = m.priority;
//Console.WriteLine("vertix found , new priority : " + _collection[i].priority + " index : " + i);
HeapifyUp(i);
}
}
}
public List<Vector2> UniformCostSearch(int from, int to)
{
List<MinHeapObject> ListOfHObjects = new List<MinHeapObject>();
List<int> Previous = new List<int>(Nodes.Count);
MinHeap Heap = new MinHeap();
MinHeapObject Root = new MinHeapObject(0, from);
for (int i = 0; i < Nodes.Count(); i++)
{
Previous.Add(-1);
if (i != from)
{
// Add infinity and node to the Heap
MinHeapObject CurrentObject = new MinHeapObject(Int32.MaxValue, i);
Heap.Insert(CurrentObject);
ListOfHObjects.Add(CurrentObject);
}
else
{
//Insert the root to the Heap with distance =0
Heap.Insert(Root);
ListOfHObjects.Add(Root);
}
}
while (Heap.Count > 0)
{
MinHeapObject Current = Heap.ExtractMinimum();
if (Current.priority == int.MaxValue) // if priority is infinity then break
{
break;
}
for (int i = 0; i < Nodes[Current.vertix].AdjacencyList.Count; i++)
{
int index = Nodes[Current.vertix].AdjacencyList[i];
if (Heap.isMember(new MinHeapObject(-1, index)))
{
int AltDistance = Current.priority + (weights[Current.vertix, index]);
if (AltDistance < ListOfHObjects[index].priority)
{
ListOfHObjects[index].priority = AltDistance;
Previous[index] = Current.vertix;
// Console.WriteLine("Updated New parent of " + index + " is " + Current.vertix);
Heap.decreasekey(ListOfHObjects[index]);
}
}
}
}
var RetList = new List<int>();
var VecList = new List<Vector2>();
int u = to;
Console.WriteLine("Path Start\n ");
while (u >= 0 && Previous[u] != -1 && u != from)
{
//Console.WriteLine(u);
VecList.Add(Nodes[u].Location);
RetList.Add(u);
u = Previous[u];
Console.WriteLine(u);
}
if (u != -1)
VecList.Add(Nodes[u].Location);
Console.WriteLine("Path End\n");
// RetList.Reverse();
InitializeCriticalPoints(RetList, from, to);
// Environment.Exit(0);
return VecList;
}