http://www.perlmonks.org?node_id=776637


in reply to scale of large data file and output them in certain format

... the program has to meet: 1. Your program should scale for files of any size, that is, if both files had 200,000 records your program should not run out of memory! Speed is not a requirement, but you should comment on the performance. 2. There are two parts to the program: the data merging and the presentation. Keep these parts clearly separated in your code.

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