Get Max Value of overlapping times in a list of Start and End Times

Question

I am trying to get a count of the max value of times where the times intersect.

The expected result that I want need from the code example below should be 4.

There are a total of 8 times, there are 6 values that intersect in total, a group of 4, and a group of 2.

What I am trying to get is the max value of intersections but just cant get it to work.

This is the code as it stands at the moment.

void Main()
{
var times = new List<Times> {
new Times
        {
            Start = DateTime.Now,
            End = DateTime.Now.AddMinutes(10)
        },
new Times
        {
            Start = DateTime.Now,
            End = DateTime.Now.AddMinutes(10)
        },
new Times
        {
            Start = DateTime.Now.AddMinutes(2),
            End = DateTime.Now.AddMinutes(10)
        },

new Times
        {
            Start = DateTime.Now.AddMinutes(15),
            End = DateTime.Now.AddMinutes(35)
        },
new Times
        {
            Start = DateTime.Now.AddMinutes(25),
            End = DateTime.Now.AddMinutes(42)
        },
new Times
        {
            Start = DateTime.Now.AddMinutes(43),
            End = DateTime.Now.AddMinutes(50)
        },
new Times
        {
            Start = DateTime.Now.AddMinutes(55),
            End = DateTime.Now.AddMinutes(89)
        },
new Times
        {
            Start = DateTime.Now.AddMinutes(2),
            End = DateTime.Now.AddMinutes(12)
        }
};


times.OrderBy(x => x.Start);

var overlappingEvents =
                        (
                        from e1 in times
                        where times
                            .Where(e2 => e1 != e2)
                            .Where(e2 => e1.Start <= e2.End)
                            .Where(e2 => e1.End >= e2.Start)
                            .Any()
                        select e1).ToList();

overlappingEvents.OrderBy(x => x.Start);
overlappingEvents.Distinct().OrderBy(x => x.Start);
overlappingEvents.Distinct().OrderBy(x => x.Start).Count();

}

public class Times
{
public DateTime Start { get; set; }
public DateTime End { get; set; }
}

This is the output of the times object

Start               |  End

05/04/2017 08:38:57 |  05/04/2017 08:48:57 

05/04/2017 08:38:57 |  05/04/2017 08:48:57 

05/04/2017 08:40:57 |  05/04/2017 08:48:57 

05/04/2017 08:40:57 |  05/04/2017 08:50:57 

05/04/2017 08:53:57 |  05/04/2017 09:13:57 

05/04/2017 09:03:57 |  05/04/2017 09:20:57 

05/04/2017 09:21:57 |  05/04/2017 09:28:57 

05/04/2017 09:33:57 |  05/04/2017 10:07:57 

This is the output of the overlapping object ( I have added the line where the intersect stops)

Start               |  End

05/04/2017 08:38:57 | 05/04/2017 08:48:57 

05/04/2017 08:38:57 | 05/04/2017 08:48:57 

05/04/2017 08:40:57 |  05/04/2017 08:48:57 

05/04/2017 08:40:57 |  05/04/2017 08:50:57 


---------------------------------------

05/04/2017 08:53:57 |  05/04/2017 09:13:57

05/04/2017 09:03:57 |  05/04/2017 09:20:57

I would be very grateful if someone can help me get the Max value of the intersections.

Thanks

Answer 1

Try this. I'm assuming that two intervals are overlapping if they have at least one common point (i.e start of ore interval is equal to the end of another interval).

void Main()
{
    var times = new List<Times> {
    new Times
        {
            Start = DateTime.Now,
            End = DateTime.Now.AddMinutes(10)
        },
    new Times
        {
            Start = DateTime.Now,
            End = DateTime.Now.AddMinutes(10)
        },
    new Times
        {
            Start = DateTime.Now.AddMinutes(2),
            End = DateTime.Now.AddMinutes(10)
        },
    new Times
        {
            Start = DateTime.Now.AddMinutes(15),
            End = DateTime.Now.AddMinutes(35)
        },
    new Times
        {
            Start = DateTime.Now.AddMinutes(25),
            End = DateTime.Now.AddMinutes(42)
        },
    new Times
        {
            Start = DateTime.Now.AddMinutes(43),
            End = DateTime.Now.AddMinutes(50)
        },
    new Times
        {
            Start = DateTime.Now.AddMinutes(55),
            End = DateTime.Now.AddMinutes(89)
        },
    new Times
        {
            Start = DateTime.Now.AddMinutes(2),
            End = DateTime.Now.AddMinutes(12)
        }
    };

    var overlaps = times.Select(t1 => times.Count(t2 => IsOverlapping(t1, t2))).Max();
}

bool IsOverlapping(Times t1, Times t2)
{
    if (t1.Start >= t2.Start && t1.Start <= t2.End)
    {
        return true;
    }

    if (t1.End >= t2.Start && t1.End <= t2.End)
    {
        return true;
    }

    if (t2.Start >= t1.Start && t2.Start <= t1.End)
    {
        return true;
    }

    if (t2.End >= t1.Start && t2.End <= t1.End)
    {
        return true;
    }

    return false;
}

public class Times
{
    public DateTime Start { get; set; }
    public DateTime End { get; set; }
}

IsOverlapping function can be simplified if you can change Times class:

bool IsOverlapping(Times t1, Times t2)
{
    return t1.Contains(t2.Start) || t1.Contains(t2.End) || t2.Contains(t1.Start) || t2.Contains(t1.End);
}

public class Times
{
    public DateTime Start { get; set; }
    public DateTime End { get; set; }

    public bool Contains(DateTime date)
    {
        return date >= Start && date <= End;
    }
}

Answer 2

Add one more property to the class

   public class Times
   {
       public DateTime Start { get; set; }
       public DateTime End { get; set; }
       public TimeSpan Gap { get; set; }
   }

Calculate the gap

   times.OrderBy(x => x.Start);

   for (int i = 0; i < times.Count-1; i++)
   {
      times[i].Gap = times[i+1].Start - times[i].End;
   }

   times.OrderByDescending(x => x.Gap);