My first approach for 2 strings would be a binary search. If each string is of length L, start by comparing the substrings from 0 to L/2. Then, depending on whether they match, either compare the substrings to L/4 or 3L/4, etc. This should give the correct result in log_2(L) steps, but bear in mind that each step requires 2 substring ops which may not be particularly cheap.

For the large number of pairs of strings consisting of only 2 chars "a" and "b" I'd think about assigning them into hash bins based on initial char sets. Each set you create should halve the number of other operations.

In reply to Re: String matching idea by hippo
in thread String matching idea by baxy77bax

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