问如何找到两组非连续时间的交集？

EN

// Finds ones with absolutely no overlap
var unmodified = shifts.Where(s => !exceptions.Any(e => s.Start < e.End && s.End > e.Start));

// Finds ones entirely overlapped
var overlapped = shifts.Where(s => exceptions.Any(e => e.End >= s.End && e.Start <= s.Start));

// Adjusted shifts
var adjusted = shifts.Where(s => !unmodified.Contains(s) && !overlapped.Contains(s))
                        .Select(s => new Shift
                        {
                            Start = exceptions.Where(e => e.Start <= s.Start && e.End > s.Start).Any() ? exceptions.Where(e => e.Start <= s.Start && e.End > s.Start).First().End : s.Start,
                            End = exceptions.Where(e => e.Start < s.End && e.End >= s.End).Any() ? exceptions.Where(e => e.Start < s.End && e.End >= s.End).First().Start : s.End
                        });

var newShiftSet = unmodified.Union(overlapped).Union(adjusted);

var orderedShifts = ShiftSets.OrderBy(x=>x.StartDate).ToList();

var compactShifts = new List<Shift>();
compactShifts.Add(orderedShifs[0]);

foreach (var item in orderedShift)
{
    if (item.Start <= compactShifts[compactShifts.Count-1].End 
        && item.End > compactShifts[compactShifts.Count-1].End)
    {
        compactShifts[compactShifts.Count-1].End = item.End;
    } 
    else if (item.Start > compactShifts[compactShifts.Count-1].End)
      compactShifts.Add(item);
}  

//run similar procedure for schedule exceptions to create compact schedules.

var validShifts = new List<Shift>();

foreach (var item in compactShifts)
{
   var shiftCheatingPart = compactExceptions
                          .FirstOrDefault(x=>x.Start < item.Start 
                                         && x.End > item.End)
   if (shiftCheatingPart != null)
   {
       if (item.End <= shiftCheatingPart.End)
         continue;

       validShifts.Add(new Shift{Start = shiftCheatingPart.End,End = item.End);
   }
}

var totalTimes = validShifts.Sum(x=>x.End.Sunbtract(x.Start).TotalHours);