You have enough unique conditions that a standard out of the box solution may not be available.

Check out this lecture on Dynamic Programing, for how to roll your own algorithm.

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-006-introduction-to-algorithms-fall-2011/lecture-videos/lecture-19-dynamic-programming-i-fibonacci-shortest-paths/

In reply to Re: How do you match a stretch of at least N characters by stall
in thread How do you match a stretch of at least N characters by Anonymous Monk

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