/// <summary>
/// Returns the competeCollection - thisCollection
/// </summary>
/// <returns></returns>
public RangeCollection Complement(long fullRangeBegin, long fullRangeEnd)
{
RangeCollection result = new RangeCollection();
long rangeLeftToCoverBegin = fullRangeBegin;
foreach (KeyValuePair <long, long> range in Ranges)
{
long start = range.Key;
long last = range.Value;
if (start > rangeLeftToCoverBegin)
{
result.AddRange(rangeLeftToCoverBegin, Math.Min(start - 1, fullRangeEnd));
}
rangeLeftToCoverBegin = Math.Max(rangeLeftToCoverBegin, last + 1);
if (rangeLeftToCoverBegin > fullRangeEnd)
{
break;
}
}
if (rangeLeftToCoverBegin <= fullRangeEnd)
{
result.AddRange(rangeLeftToCoverBegin, fullRangeEnd);
}
return(result);
}
/// <summary>
/// Returns a collection of elements at what would be the i'th element for i \in [startIdx,lastIdx]. startIdx and lastIdx are 0-based.
/// </summary>
private RangeCollection ElementsAt(long startIndex, long lastIndex)
{
if (lastIndex < startIndex || startIndex < 0 || lastIndex >= Count())
{
throw new ArgumentOutOfRangeException(string.Format("{0}-{1} must be a non-empty range that falls between 0 and {2}", startIndex, lastIndex, Count() - 1));
}
RangeCollection result = new RangeCollection();
long countSoFar = 0;
foreach (KeyValuePair <long, long> range in Ranges)
{
long rangeLength = range.Value - range.Key + 1;
if (startIndex - countSoFar < rangeLength)
{
long start = range.Key + startIndex - countSoFar;
long lastIfContinuousRange = range.Key + lastIndex - countSoFar;
long last = Math.Min(range.Value, lastIfContinuousRange); // if startIdx-lastIdx falls completely in range, then take 2nd entry.
result.AddRange(start, last);
if (lastIfContinuousRange <= range.Value) // if this range covers the remaining indeces, we're done.
{
return(result);
}
else
{
startIndex = countSoFar + rangeLength;
}
}
countSoFar += rangeLength;
}
throw new NotImplementedException("If we get here, then there's a bug in the implementation.");
}
