/// <summary>
/// Generate in memory.
/// </summary>
/// <returns></returns>
static List<Segment> GenerateList()
{
/// The whole bunch, or the next bunch, of segments.
AllSegments = new List<Segment>();
/// Start with this.
/// (Todo: Perhaps read from the database.)
long nextAvailableValue = 1L;
for (int iteration = 0; iteration < ParametersOfExperiment.NoMoreIterationsThan; iteration++) {
// Create the next segment.
Segment s = new Segment().CreateNewSegmentOfRandomSize(nextAvailableValue,
ParametersOfExperiment.MaxSegmentSize, ParametersOfExperiment.NoLargerValueThan);
AllSegments.Add(s);
// Split zero or more segments.
int numberOfSplits = R.Next(0, ParametersOfExperiment.MaxNumberOfConsecutiveSplits);
for (int split = 0; split < numberOfSplits; split++) {
// Choose a random segment, split it, and update the list of segments.
int xSegmentToSplit = R.Next(1, AllSegments.Count);
AllSegments.SplitSegment(xSegmentToSplit);
}
// Stop if reached the max value.
nextAvailableValue += s.Size;
if (nextAvailableValue > ParametersOfExperiment.NoLargerValueThan) { break; }
}
return AllSegments;
}
public void TestSegment()
{
Segment s;
s = new Segment();
Assert.IsFalse(s.IsValid);
s.CreateWithEndPoints(3, 2);
Assert.IsFalse(s.IsValid);
Assert.IsFalse(s.Size > 0);
s.CreateWithEndPoints(7, 7);
Assert.IsTrue(s.IsValid);
Assert.AreEqual(1, s.Size);
int size = int.MaxValue; // heh
s.CreateWithEndPoints(1, size);
Assert.IsTrue(s.IsValid);
Assert.AreEqual(size, s.Size);
// CreateNextSegmentOfRandomSize
// TODO
}
/// <summary>
/// The segment is split into two.
/// Left part is corrected (the split point is the new right end);
/// right part is appended (the split point is the new left end).
/// Null on an error!
/// </summary>
public static List<Segment> SplitSegment(this List<Segment> list, int indexOfSegmentToSplit)
{
if (null == list || indexOfSegmentToSplit >= list.Count) { return null; }
Segment s = list[indexOfSegmentToSplit];
if (s.Size == 1) { return list; } // cannot split
int splitAt = R.Next(0, (int) (s.Right - s.Left)); // size is expected to fit in int
// L..R is split as S. This means:
// 1) if S < R, let T = S+1. Then:
// one segment is L..S
// another is T..R
// 2) Otherwise, S=R. Let U = S-1 = R-1. Then:
// one segment is L..U
// another is R..R
Segment sAnother = new Segment();
long pointL = s.Left;
long pointR = s.Right;
long pointS, pointT, pointU;
pointS = pointL + splitAt;
if (splitAt < s.Size) {
pointT = pointS + 1L;
sAnother.CreateWithEndPoints(pointT, pointR);
s.CreateWithEndPoints(pointL, pointS);
} else {
pointU = pointR - 1;
sAnother.CreateWithEndPoints(pointR, pointR);
s.CreateWithEndPoints(pointL, pointU);
}
// Replace s; add sAnother.
list[indexOfSegmentToSplit] = s;
list.Add(sAnother);
return list;
}
