The beauty of a hash is that Perl doesn't need to compare the string to every key in the hash. It computes the hash for the string and looks in the bucket for that hash. In a well balanced hash, there should only be one key in that hash. The string needs to be compared against the key(s) in the bucket.

The hash replaces multiple comparisons with a hash calculation and usually one comparison.

In reply to Re: Re: Re: Re: how can I speed up this perl?? by iburrell
in thread how can I speed up this perl?? by Anonymous Monk

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