Count Text String Occurrence Across 2 Column Array But Only Count Text String Once if in Adjacent Cell

[bearwires]

I have a data table with multiple columns.
I need to count the number of occurrences of names in the range --> Summary!$C$3:$D$10000.
The name list is located on Sheet1!$A$2:$A$8
I want the total count to be Sheet1!$B$2:$B$8

If the same name is shown in the adjacent column cell, I only want to count that name once.

It is this part which is causing me a headache.

I can count all occurrences in the entire range, using

=COUNTIF(Summary!$C$3:$D$10000,Sheet1!$A2)

.
When a name occurs twice on the same row, the formula obviously doens't take that into account.

C​	D​
Bob Smith	Dave Jones
Dave Jones	Bob Smith
Ryan Evans	Ivor Biggun
Chris Peacock	Mike Hunt
Ivor Biggun	Peter Schlong
Mike Hunt	Oscar Reynolds
Chris Peacock	Chris Peacock
Peter Schlong	Ryan Evans
Oscar Reynolds	Chris Peacock
Chris Peacock	Mike Hunt

This is the result I need the formula show based on the above data set:

Chris Peacock = 4
Bob Smith = 2
Dave Jones = 2
Ryan Evans = 2
Ivor Biggun = 2
Mike Hunt = 2
Peter Schlong = 2
Oscar Reynolds = 2


Can someone give me a hand to solve this issue please?

Thanks

 

[Joe4]

One way:

=COUNTIF(Summary!$C$3:$D$10000,Sheet1!$A2)-COUNTIFS(Summary!$C$3:$C$10000,Sheet1!$A2,Summary!$D$3:$D$10000,Sheet1!$A2)