This is how I would proceed:

Create a hash. The keys will be the reaction numbers. The values will be hash references with two keys: 'reactants' and 'products'. The values will be hash references again, use reactants and products respectively as keys. The values can stay undefined. After the hashes are filled, just go over the keys and print out all the tuples in nested loops.

In reply to Re: correlation between two inputt files by choroba
in thread correlation between two inputt files by himanshuyadav

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