Calculating overlap times between two sets of time stamps for different sets of dates

[phrozen888]

Hello,

This is my first post on this forum and I am at a complete loss of how to proceed with calculating this.

I have two sets of data (#1) and (#2) with their own respective start and end date/time stamps. For example:
[TABLE="width: 500"]
<tbody>[TR]
[TD]Start time (#1)[/TD]
[TD]End time (#1)[/TD]
[TD]Start time (#2)[/TD]
[TD]End time (#2)[/TD]
[TD]Overlap time (hh:mm)[/TD]
[/TR]
[TR]
[TD][TABLE="width: 163"]
<tbody>[TR]
[TD="align: right"]1/4/16 1:56 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 131"]
<tbody>[TR]
[TD="align: right"]1/4/16 1:57 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 97"]
<tbody>[TR]
[TD]1/4/16 1:21 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 97"]
<tbody>[TR]
[TD]1/4/16 3:37 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD]0:01[/TD]
[/TR]
[TR]
[TD][TABLE="width: 163"]
<tbody>[TR]
[TD="align: right"]2/4/16 12:36 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 131"]
<tbody>[TR]
[TD="align: right"]2/4/16 12:59 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 97"]
<tbody>[TR]
[TD]2/4/16 12:27 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 97"]
<tbody>[TR]
[TD]2/4/16 12:40 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD]0:13[/TD]
[/TR]
[TR]
[TD][TABLE="width: 163"]
<tbody>[TR]
[TD="align: right"][TABLE="width: 159"]
<tbody>[TR]
[TD="align: right"]3/12/16 9:20 AM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 131"]
<tbody>[TR]
[TD="align: right"][TABLE="width: 159"]
<tbody>[TR]
[TD="align: right"]3/12/16 10:22 AM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 95"]
<tbody>[TR]
[TD]3/3/16 2:32 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 95"]
<tbody>[TR]
[TD]3/3/16 2:53 PM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]-[/TD]
[TD]-[/TD]
[TD][TABLE="width: 95"]
<tbody>[TR]
[TD]3/4/16 10:09 AM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 95"]
<tbody>[TR]
[TD]3/4/16 10:41 AM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]-[/TD]
[TD]-[/TD]
[TD][TABLE="width: 95"]
<tbody>[TR]
[TD]3/12/16 9:03 AM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD][TABLE="width: 95"]
<tbody>[TR]
[TD]3/12/16 11:38 AM[/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]
[/TD]
[TD]1:02[/TD]
[/TR]
</tbody>[/TABLE]

So the two sets of data are different in list size, for example #1 has 3 entries, #2 has 5 entries.

What I want to figure out is, for each start/end in list #1, how long is that duration overlapped in any entry in list #2?

Thanks in advance!