This is awesome! Thank you so much GrandFather. I tried with the following data:

 __DATA__
NP_01 NP_02
NP_02 NP_01
NP_01 NP_03
NP_03 NP_01
NP_02 NP_03
NP_03 NP_02
NP_04 NP_05
NP_06 NP_07
NP_07 NP_06

This prints:
NP_01 NP_02
NP_01 NP_03
NP_06 NP_07
4

[download]

I want the output to be like this instead:

NP_01 NP_02
NP_01 NP_03
3
NP_06 NP_07
1

[download]

3 for the presence of all three NP_01-NP_02, NP_01-NP_03, NP_02-NP_03 possible pairs in the file. Lets say, if NP_02-NP_03 combination was not present in the file then the number should become 2 showing that NP_02-NP_03 combo does not exist in the file. Any suggestion how can I get this from your code.

Example in case when NP_02-NP_03 reciprocal pair does not exist in the file and the required output

 __DATA__
NP_01 NP_02
NP_02 NP_01
NP_01 NP_03
NP_03 NP_01
NP_04 NP_05
NP_06 NP_07
NP_07 NP_06

prints:
NP_01 NP_02
NP_01 NP_03
 2 [not present in NP_02 NP_03]

NP_06 NP_07
1

[download]

In reply to Re^2: help needed in modifying the code for counting possible combinations by BhariD
in thread help needed in modifying the code for counting possible combinations by BhariD

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