This method's run time is O(NlogN) or therabouts, while your attempt is O(N**2).

I think your method is actually O(N+M) as you iterate each array once and johnirl's is O(N*M) because he iterates one array for each element in the other.

The difference in array size might be significant. That is why I used two different variables: N and M.

Update: A short /msg exchange with Zaxo prompted me to point out that searches and updates on hashes are expected to be O(1). That is, assuming that the hash function is a good one for your data. I believe it is a reasonable assumption to make here.

-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Re: Comparing Two arrays by sauoq
in thread Comparing Two arrays by johnirl

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