I want to generate strings of length N, draw from a set of M chars, but with no more than two of any given char consecutively.

Examples:

set ABCDEF;
length 12;

Valid:
ABCDEFABCDEF
AABBCCDDEEFF

Invalid:
AAABCDEFABCD

[download]

I don't know whether this is tougher than it first appears, or I'm just having a bad head day. but my attempts so far involve cumbersome loops with the setting and resetting of myriad flags.

Any thoughts on a clean way to do this?

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In reply to Random data generation. by BrowserUk

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