c1 is overlapping b and a2 ranges.

How many keys do you expect the hash to have?

This approach could be difficult to handle... If you want to add many spans, you will end with many rows with only one X for each span.

Also, if you want to add more than 9 spans with an X in the same position, the result string won't be enough.

In reply to Re: Efficient algorithm needed to split Set::IntSpan objects by vitoco
in thread Efficient algorithm needed to split Set::IntSpan objects by tim.bunce

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