private static void UpdateSolutionMatrix(List <Item> items, Bag bag, SolutionMatrix solutionMatrix)
{
for (int col = 0; col < items.Count; col++)
{
for (int row = 0; row <= bag.RemainingCapacity; row++)
{
var item = items[col];
if (col == 0)
{
if (item.Weight <= row)
{
solutionMatrix.UpdateValue(row, col, item.Value);
}
}
else
{
if (item.Weight <= row)
{
int value = Math.Max(solutionMatrix.GetValue(row, col - 1),
item.Value + solutionMatrix.GetValue(row - item.Weight, col - 1));
solutionMatrix.UpdateValue(row, col, value);
}
else
{
solutionMatrix.UpdateValue(row, col, solutionMatrix.GetValue(row, col - 1));
}
}
}
}
}
private void TraceBackSolution(Bag bag, List <Item> items, SolutionMatrix solutionMatrix)
{
int row = bag.RemainingCapacity;
for (int col = items.Count - 1; col >= 0; col--)
{
if (col == 0)
{
if (solutionMatrix.GetValue(row, col) > 0)
{
_itemRepository.UpdateSolution(items[col]);
bag.UpdateSolution(items[col]);
}
}
else
{
if (solutionMatrix.GetValue(row, col) != solutionMatrix.GetValue(row, col - 1))
{
_itemRepository.UpdateSolution(items[col]);
bag.UpdateSolution(items[col]);
row -= items[col].Weight;
}
}
}
}
public void Optimize()
{
if (!AlgorithmPicker.ShouldRunOnThisDataSet(this, _itemRepository.GetItemCount()))
{
return;
}
var bag = _bagRepository.GetBag();
var items = _itemRepository.GetAllItems();
var solutionMatrix = new SolutionMatrix(bag.RemainingCapacity + 1, items.Count);
UpdateSolutionMatrix(items, bag, solutionMatrix);
TraceBackSolution(bag, items, solutionMatrix);
}
