vba to check if dates overlap

[LFKim2018]

how do we check via VBA or formula if dates overlap each other?
date1: start date: 9-9-2018 end date: 10-8-2018
date2: start date: 9-22-2018 end date: 10-20-2018
date3: start date: 10-10-2018 end date: 11-15-2018
date2 overlaps with date1 while date3 overlaps with date2 etc
many many thanks

 

[Yongle]

Excel 2016 (Windows) 32 bit
[TABLE="class: head"]
<tbody>[TR="bgcolor: #E0E0F0"]
[TH][/TH]
[TH]

A​

[/TH]
[TH]

B​

[/TH]
[TH]

C​

[/TH]
[/TR]
[TR="bgcolor: #FFFFFF"]
[TD="bgcolor: #E0E0F0"]

1​

[/TD]
[TD]start[/TD]
[TD]end[/TD]
[TD][/TD]
[/TR]
[TR="bgcolor: #FFFFFF"]
[TD="bgcolor: #E0E0F0"]

2​

[/TD]
[TD]

09-09-2018​

[/TD]
[TD]

10-08-2018​

[/TD]
[TD]

TRUE​

[/TD]
[/TR]
[TR="bgcolor: #FFFFFF"]
[TD="bgcolor: #E0E0F0"]

3​

[/TD]
[TD]

09-22-2018​

[/TD]
[TD]

10-20-2018​

[/TD]
[TD]

TRUE​

[/TD]
[/TR]
[TR="bgcolor: #FFFFFF"]
[TD="bgcolor: #E0E0F0"]

4​

[/TD]
[TD]

10-10-2018​

[/TD]
[TD]

11-15-2018​

[/TD]
[TD]

TRUE​

[/TD]
[/TR]
</tbody>[/TABLE]
[TABLE="class: grid"]
<tbody>[TR]
[TD]Sheet: Sheet5[/TD]
[/TR]
</tbody>[/TABLE]

Formula in C2
Excel 2016 (Windows) 32 bit
[TABLE="class: head"]
<tbody>[TR="bgcolor: #E0E0F0"]
[TH][/TH]
[TH]

C​

[/TH]
[/TR]
[TR="bgcolor: #FFFFFF"]
[TD="bgcolor: #E0E0F0"]

2​

[/TD]
[TD]

=SUMPRODUCT((A2<=B:B)*(B2>A:A))>1​

[/TD]
[/TR]
</tbody>[/TABLE]
[TABLE="class: grid"]
<tbody>[TR]
[TD]Sheet: Sheet5[/TD]
[/TR]
</tbody>[/TABLE]

Conditional formatting
If you prefer to use conditional formatting - here is a tutorial displaying that method

 

[LFKim2018]

Mr. Yongle
thank you very much for your reply..