If I understood you correctly, you don't need nested loops to do what you want. And you also don't need to store your file in an array in the first place. You can just read your input file, store the data from your first line in an array or a hash; then you go to the next line, if it meets the criteria of what you have already stored, add to the existing hash entry, otherwise create a new hash entry, and so on. In other word, you need only one pass through your file to get all what you need into the hash. At the end, print the hash content or do whatever you need with it.

In reply to Re: Iterating through an array using multiple loops and removing array elements by Laurent_R
in thread Iterating through an array using multiple loops and removing array elements by BiochemPhD

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