public Knapsack ReadKnapsack()
{
if (_streamReader.EndOfStream || _solutionStreamReader != null && _solutionStreamReader.EndOfStream)
{
_streamReader.Close();
_solutionStreamReader?.Close();
return null;
}
var line = _streamReader.ReadLine();
var solutionLine = _solutionStreamReader?.ReadLine();
if (solutionLine != null && string.IsNullOrEmpty(solutionLine) || string.IsNullOrEmpty(line))
{
_streamReader.Close();
_solutionStreamReader?.Close();
return null;
}
var splitted = line.Split(' ');
var solutionSplitted = solutionLine?.Split(' ');
if (splitted.Length < 4) throw new FormatException("Invalid format of input data on line " + _lineNumber);
var n = Parse(splitted[1]);
if (n < 0) throw new FormatException("Invalid format of input data on line " + _lineNumber);
var capacity = Parse(splitted[2]);
var values = new int[n * 2];
_lineNumber++;
for (var i = 0; i < n; i++)
{
values[i * 2] = Parse(splitted[3 + i * 2]);
values[i * 2 + 1] = Parse(splitted[3 + i * 2 + 1]);
}
Knapsack knapsack = new Knapsack(values, capacity, 0);
int solution;
if (false && solutionSplitted != null)
{
solution = Parse(solutionSplitted[2]);
}
else
{
Algorithm algo = new CostDecomposition();
Console.WriteLine($"Calculating correct solution using algo {algo.ToString()}");
algo.Knapsack = knapsack;
solution = algo.Solve();
}
knapsack.Solution = solution;
return knapsack;
}
protected override Answer Calculate()
{
Knapsack bag = new Knapsack(MaxWeight);
MaxValueItems = bag.Items.ToArray();
Explore(bag, Items.ToList());
return(new Answer
{
Items = MaxValueItems,
ExecCount = CallCount
});
}
static void Main(string[] args)
{
List <Item> list = new List <Item>();
//item value - weight
list.Add(new Item(10, 1));
list.Add(new Item(5, 2));
list.Add(new Item(40, 8));
list.Add(new Item(45, 10));
Knapsack sack = new Knapsack(list, 10);
Console.WriteLine($"Greedy: {sack.Greedy()}");
Console.WriteLine($"Brute force: {sack.Iterative()}");
Console.WriteLine($"Divide & conquer: {sack.Recursive(sack.MaxWeight, 0)}");
Console.WriteLine($"Dynamic: {sack.Dynamic()}");
}
static void Main(string[] args)
{
int W = 11;
int[] V = new int[4] {
30, 14, 16, 9
};
int[] Weights = new int[4] {
6, 3, 4, 2
};
Random objR = new Random();
Knapsack objK = new Knapsack();
//for (int i = 0; i < V.Length; i++)
//{
// V[i] = objR.Next(1, 10);
// Weights[i] = objR.Next(1, 10);
//}
Console.WriteLine(objK.ComputeDPKnapsack(W, V, Weights));
Console.ReadLine();
}
private static void Main(string[] args)
{
Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo();
Action <object> write = Console.Write;
var stopwatch = new Stopwatch();
stopwatch.Start();
write("Running ..\n\n");
var rand = new Random();
// -------------- Insert data here
const int N = 10;
const int maxWeight = 20;
var items = new List <Item>();
for (var i = 0; i < N; i++)
{
items.Add(new Item {
w = rand.Next(1, 10), v = rand.Next(1, 100)
});
}
Knapsack.Init(items, maxWeight);
Knapsack.Run();
stopwatch.Stop();
write("Done\n\n");
Knapsack.PrintPicksMatrix(write);
Knapsack.Print(write, true);
write(string.Format("\n\nDuration: {0}\nPress a key to exit\n",
stopwatch.Elapsed.ToString()));
Console.ReadKey();
}
public void Explore(Knapsack knapsack, List <Item> options)
{
//篩選小於背包剩餘可負重的物品一一嘗試
//這裡直接用Where過濾，若要提高效能需再優化
foreach (var item in options.Where(o => o.Weight <= knapsack.AllowedWeight))
{
CallCount++;
knapsack.AddItem(item); //放入物品
if (knapsack.CurrentValue > MaxValue) //若超越最高記錄就記錄
{
MaxValueItems = knapsack.Items.ToArray();
MaxValue = knapsack.CurrentValue;
}
if (!Duplicatable) //若不允許物品重複，已放入背包的項目需移出選項
{
Explore(knapsack, options.Except(new Item[] { item }).ToList());
}
else
{
Explore(knapsack, options.ToList());
}
knapsack.RemoveItem(item);
}
}
public Knapsack ReadKnapsack()
{
if (_streamReader.EndOfStream || _solutionStreamReader != null && _solutionStreamReader.EndOfStream)
{
_streamReader.Close();
_solutionStreamReader?.Close();
return(null);
}
var line = _streamReader.ReadLine();
var solutionLine = _solutionStreamReader?.ReadLine();
if (solutionLine != null && string.IsNullOrEmpty(solutionLine) || string.IsNullOrEmpty(line))
{
_streamReader.Close();
_solutionStreamReader?.Close();
return(null);
}
var splitted = line.Split(' ');
var solutionSplitted = solutionLine?.Split(' ');
if (splitted.Length < 4)
{
throw new FormatException("Invalid format of input data on line " + _lineNumber);
}
var n = Parse(splitted[1]);
if (n < 0)
{
throw new FormatException("Invalid format of input data on line " + _lineNumber);
}
var capacity = Parse(splitted[2]);
var values = new int[n * 2];
_lineNumber++;
for (var i = 0; i < n; i++)
{
values[i * 2] = Parse(splitted[3 + i * 2]);
values[i * 2 + 1] = Parse(splitted[3 + i * 2 + 1]);
}
Knapsack knapsack = new Knapsack(values, capacity, 0);
int solution;
if (false && solutionSplitted != null)
{
solution = Parse(solutionSplitted[2]);
}
else
{
Algorithm algo = new CostDecomposition();
Console.WriteLine($"Calculating correct solution using algo {algo.ToString()}");
algo.Knapsack = knapsack;
solution = algo.Solve();
}
knapsack.Solution = solution;
return(knapsack);
}