Okay, part deux. Hash look-ups are the way to solve this problem. I withdraw the question.

Okay, sorting both files appears to be the only answer I can find... Is there another?

I have two large (10Mg plus) files of words, one file contains essentially just words, the other words and their pronunciations.

I want to discover and store how many of the words in the file without pronunciations have their pronunciations in the other file.

The first way, and only way, I can think of to do this is to check each word in the file without pronunciations against every word in the pronunciation file, but that will result in 10M X 10M comparisons and be very costly in time.

Is there another way? I believe I have seen one, but cannot remember it.

Thank you.

In reply to Comparing large files by Herbert37

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