/// <summary>
/// metóda pre spracovanie uzlu stromu
/// </summary>
/// <param name="nextUsed"></param>
public void Process(bool nextUsed)
{
myUsed[myProcessedIndex] = nextUsed ? 1 : 0;
ComputeValueAndWeight();
if (!IsHeavier && myValue > KnapsackNode.BestValue)
{
if (KnapsackNode.BestNode != null)
{
KnapsackNode.BestNode.IsBestNode = false;
}
KnapsackNode.BestValue = myValue;
KnapsackNode.BestNode = this;
IsBestNode = true;
}
double futureValue = myValue;
for (int i = myProcessedIndex + 1; i < myItems.Count; i++)
{
futureValue += myItems.Count;
}
if (!IsHeavier && !AreAllUsed && futureValue > KnapsackNode.BestValue)
{
myLeftChild = new KnapsackNode(myItems, myUsed);
myLeftChild.Process(true);
myRightChild = new KnapsackNode(myItems, myUsed);
myRightChild.Process(false);
}
}
/// <summary>
/// metóda pre spustenie algoritmu
/// </summary>
public void Start()
{
if (myItems == null || myItems.Count == 0)
{
return;
}
try
{
int tempVarNoItems = 0;
double tempVarAllItems = 0;
foreach (KnapsackItem item in myItems)
{
if (item.Weight > KnapsackNode.MaxWeight)
{
tempVarNoItems++;
}
tempVarAllItems += item.Weight;
}
if (tempVarNoItems == myItems.Count)
{
Solution = "Do batoha sa nezmesí žiaden predmet";
return;
}
if (tempVarAllItems < KnapsackNode.MaxWeight)
{
Solution = "Do batoha sa zmestia všetky predmety";
return;
}
myItems.Sort();
//predmet 1
KnapsackNode rootLeft = new KnapsackNode(myItems);
rootLeft.Process(true);
//predmet 0
KnapsackNode rootRight = new KnapsackNode(myItems);
rootRight.Process(false);
StringBuilder builder = new StringBuilder();
builder.AppendLine("Do batoha sa zoberú predmety:");
int index = 0;
foreach (int? item in KnapsackNode.BestNode.Used)
{
if (item.HasValue && item.Value == 1)
{
builder.AppendLine(string.Format("váha = {0:0.00}, hodnota = {1:0.00}", myItems[index].Value, myItems[index].Weight));
}
index++;
}
Solution = builder.ToString();
}
catch
{
Solution = "Úlohu sa nepodarilo vyriešiť.";
}
}