static LibraryResult ComputeLibraryPotential(Library library)
{
// var watch = System.Diagnostics.Stopwatch.StartNew();
LibraryResult result = new LibraryResult()
{
Library = library
};
int productiveDays = _daysRemaining - library.SignupDuration;
if (productiveDays <= 0)
{
result.ScoreYield = 0;
return(result);
}
;
int[] notScannedBookIds = library.BookIds.Except(_alreadyScanned).ToArray();
int maxBookYield = Math.Min((productiveDays * library.ShippableBookCount), notScannedBookIds.Length);
IEnumerable <KeyValuePair <int, int> > chosenBooksWithScores = notScannedBookIds
// .AsParallel()
.Select(i => new KeyValuePair <int, int>(i, _bookScores[i]))
.OrderByDescending(pair => pair.Value)
// .AsSequential()
.Take(maxBookYield);
// IEnumerable<KeyValuePair<int, int>> chosenBooksWithScores = _bookScores
// .Where(bookScore => notScannedBookIds.Contains(bookScore.Key))
// .OrderByDescending(pair => pair.Value)
// .Take(maxBookYield);
result.ScoreYield = chosenBooksWithScores.Sum(pair => pair.Value);
result.BookIdSequence = chosenBooksWithScores.Select(pair => pair.Key);
// watch.Stop();
// var elapsedMs = watch.ElapsedMilliseconds;
// DateTime stop = DateTime.Now;
// TimeSpan timeSpan = stop - start;
// Console.WriteLine("Duration for ComputeLibraryPotential: " + new TimeSpan(watch.ElapsedTicks));
// Console.WriteLine("Computed library " + library.Id + ". Score: " + result.ScoreYield);
return(result);
}
private static void DutzuGreedy(string inputFileName)
{
Console.WriteLine("Processing file: " + inputFileName);
InputData inputData = ReadInputData(inputFileName);
Console.WriteLine("Finished reading input data. Received " + inputData.Libraries.Count + " libraries.");
_daysRemaining = inputData.DayCount;
_bookScores = inputData.BookScores;
int currentScore = 0;
List <LibraryResult> chosenLibraryResults = new List <LibraryResult>();
LibraryResult x = GetNextBestLibrary(inputData.Libraries);
while (true)
{
LibraryResult nextBestLibrary = GetNextBestLibrary(inputData.Libraries);
if (nextBestLibrary == null)
{
break;
}
if (nextBestLibrary.ScoreYield == 0)
{
break;
}
chosenLibraryResults.Add(nextBestLibrary);
inputData.Libraries.Remove(nextBestLibrary.Library);
_alreadyScanned.AddRange(nextBestLibrary.BookIdSequence);
currentScore += nextBestLibrary.ScoreYield;
_daysRemaining -= nextBestLibrary.Library.SignupDuration;
// Console.WriteLine("Next best library: " + nextBestLibrary.Library.Id + " - score: " +
// nextBestLibrary.ScoreYield + ". Remaining days: " + _daysRemaining);
}
Console.WriteLine("Total Score: " + currentScore);
WriteOutput("out_" + Path.GetFileName(inputFileName), chosenLibraryResults);
}
static LibraryResult GetNextBestLibrary(IEnumerable <Library> availableLibraries)
{
var watch = System.Diagnostics.Stopwatch.StartNew();
LibraryResult mostProfitableLibrary = availableLibraries.AsParallel()
.Select(ComputeLibraryPotential)
.OrderByDescending(libraryResult => libraryResult?.ScoreYield)
.FirstOrDefault();
// ParallelLoopResult parallelLoopResult = Parallel.ForEach(availableLibraries, library => ComputeLibraryPotential(library));
// availableLibraries.AsParallel().Select(ComputeLibraryPotential)
// .OrderByDescending(libraryResult => libraryResult.ScoreYield)
// .ToArray();
watch.Stop();
// var elapsedMs = watch.ElapsedMilliseconds;
// Console.WriteLine("Duration for GetNextBestLibrary: " + elapsedMs);
Console.WriteLine("Duration for GetNextBestLibrary: " + new TimeSpan(watch.ElapsedTicks) + " id:" + mostProfitableLibrary.Library.Id + " - score - " + mostProfitableLibrary.ScoreYield);
return(mostProfitableLibrary);
}