An obvious improvement could be to sort your array first. So you can check each value on its neighbors only reducing the tests from N*N to N*M where M is the average population of clusters more 1.

Rule One: "Do not act incautiously when confronting a little bald wrinkly smiling man."

In reply to Re: fastest way to compare numerical strings? by psini
in thread fastest way to compare numerical strings? by Anonymous Monk

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