private long CalculateScoreForVPair(bool[] lastTagsInBool, int lastSlideTagCount, Photo firstV, Photo secondV, bool[] firstVTagsInBool)
{
int score = 0;
int interSize = 0;
int commontagscount = 0;
foreach (var tagindex in firstV.TagIndexes)
{
if (lastTagsInBool[tagindex])
{
interSize++;
}
}
foreach (var tagindex in secondV.TagIndexes)
{
if (firstVTagsInBool[tagindex])
{
commontagscount++;
continue;
// not counting it again
}
if (lastTagsInBool[tagindex])
{
interSize++;
}
}
int totalTagsCount = firstV.TagIndexes.Length + secondV.TagIndexes.Length - commontagscount;
score = Math.Min(Math.Min(interSize, totalTagsCount - interSize),
lastSlideTagCount - interSize);
return(score);
}
protected override ProblemOutput Solve(ProblemInput input)
{
var allPhotos = input.Photos.ToArray();
var totalTags = input.TagCount;
var usedInASlideC = new ConcurrentDictionary <long, byte>();
var usedInASlide = new HashSet <long>();
Slide lastSlide;
////for (int i = 0; i < allPhotos.Length; i++)
////{
//// var bestScore = -1;
//// for (int j = 0; j < allPhotos.Length; j++)
//// {
//// int currScore = -1;
//// if (visited.Contains(j))
//// {
//// continue;
//// }
//// currScore = CalclateScoreForCurrentSlide(lastSlide, allPhotos[i], allPhotos[j]);
//// if (bestScore < currScore)
//// {
//// }
//// }
////}
// Build First Slide
List <Slide> slides = new List <Slide>();
if (!allPhotos.First().IsVertical)
{
lastSlide = new Slide(new List <Photo>()
{
allPhotos.First()
});
}
else
{
lastSlide = new Slide(new List <Photo>()
{
allPhotos.First(), allPhotos.Skip(1).First(_ => _.IsVertical)
});
}
slides.Add(lastSlide);
foreach (var photo in lastSlide.Images)
{
usedInASlide.Add(photo.Index);
usedInASlideC.TryAdd(photo.Index, 0);
}
var lastSlideTagsBool = new bool[input.TagCount];
var pairTagsBool = new bool[input.TagCount];
while (usedInASlide.Count != allPhotos.Length)
{
Array.Clear(lastSlideTagsBool, 0, lastSlideTagsBool.Length);
int lastSlideTagCount = 0;
foreach (var tagIndex in lastSlide.TagsIndexes)
{
lastSlideTagsBool[tagIndex] = true;
lastSlideTagCount++;
}
// build a slide
long bestScore = -1;
Slide slideToUse = null;
Parallel.ForEach(Partitioner.Create(1, allPhotos.Length), range =>
{
for (int i = range.Item1; i < range.Item2; i++)
{
if (usedInASlideC.ContainsKey(i))
{
continue;
}
// Build a slide with this photo
var potentialSlide = new Slide(new List <Photo>()
{
allPhotos[i]
});
long ScoreIfUsed = CalculateScoreForNewSlide(allPhotos[i], lastSlideTagsBool, lastSlideTagCount);
if (ParallelHelper.InterlockedExchangeIfGreaterThan(ref bestScore, ScoreIfUsed))
{
// use this
//bestScore = ScoreIfUsed;
lock (slides)
{
slideToUse = potentialSlide;
}
}
}
});
//for (int i = 1; i < allPhotos.Length; i++)
//{
// // Skip if already used
// if (usedInASlide.Contains(i))
// {
// continue;
// }
// // Build a slide with this photo
// var potentialSlide = new Slide(new List<Photo>() { allPhotos[i] });
// long ScoreIfUsed = CalculateScoreForNewSlide(allPhotos[i], lastSlideTagsBool, lastSlideTagCount);
// if (bestScore < ScoreIfUsed)
// {
// // use this
// slideToUse = potentialSlide;
// bestScore = ScoreIfUsed;
// }
//}
// if slideToUse is lonely V, find it a pair:
if (slideToUse.Images.First().IsVertical)
{
// Build Pair Bool
Array.Clear(pairTagsBool, 0, pairTagsBool.Length);
foreach (var tagindex in slideToUse.Images.First().TagIndexes)
{
pairTagsBool[tagindex] = true;
}
long bestScoreForV = -1;
Photo vPair = null;
object lockpair = new object();
Parallel.ForEach(Partitioner.Create(1, allPhotos.Length), range =>
{
for (int i = range.Item1; i < range.Item2; i++)
{
if (usedInASlideC.ContainsKey(i) || !allPhotos[i].IsVertical || i == slideToUse.Images.First().Index)
{
continue;
}
long scoreIfUsed = CalculateScoreForVPair(lastSlideTagsBool, lastSlideTagCount, slideToUse.Images.First(), allPhotos[i], pairTagsBool);
if (ParallelHelper.InterlockedExchangeIfGreaterThan(ref bestScoreForV, scoreIfUsed))
{
lock (lockpair)
{
vPair = allPhotos[i];
}
}
}
});
//for (int i = 0; i < allPhotos.Length; i++)
//{
// if (usedInASlide.Contains(i) || !allPhotos[i].IsVertical || i == slideToUse.Images.First().Index)
// {
// continue;
// }
// ////foreach (var tagIndex in allPhotos[i].TagIndexes)
// ////{
// //// pairTagsBool[tagIndex] = true;
// ////}
// long scoreIfUsed = CalculateScoreForVPair(lastSlideTagsBool, lastSlideTagCount, slideToUse.Images.First(), allPhotos[i]);
// if (bestScoreForV < scoreIfUsed)
// {
// vPair = allPhotos[i];
// bestScoreForV = scoreIfUsed;
// }
//}
if (vPair == null)
{
var vertsNotUsed = allPhotos.Where(p => p.IsVertical && !usedInASlide.Contains(p.Index)).ToArray();
}
slideToUse.Images.Add(vPair);
}
slides.Add(slideToUse);
foreach (var photo in slideToUse.Images)
{
usedInASlide.Add(photo.Index);
usedInASlideC.TryAdd(photo.Index, 0);
}
lastSlide = slideToUse;
}
return(new ProblemOutput()
{
Slides = slides
});
}
