QBIC, 33 bytes
≈instr(Z,;)<1|Z=Z+chr$(_r32,126|)
Explanation
≈instr( , )<1| WHILE InStr() can't find
; the input (cmd line string argument) as part of
Z the output (Z$, which is printed automatically on exit)
Z=Z+ add to the output
chr$( ) an ASCII character
_r32,126| with a random codepoint between 32 and 126 (incl)
Sample run:
Command line: hi
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Sandbox – LyricLy – 2017-11-05T22:38:48.140
11
Do we need to follow the described procedure to produce the output? If yes, that's an unobservable requirement, which is problematic. If not, we can generate
– Luis Mendo – 2017-11-05T23:24:52.930B
directly by prepending a non-negative numbern
of random characters toA
. The only real problem then is to know the distribution ofn
(I bet on a geometric distribution)@LuisMendo I have clarified that in the question body. – LyricLy – 2017-11-06T00:05:29.967
@LyricLy I attempted to clarify a small bit more, feel free to revert if you don't like my edit. – Rɪᴋᴇʀ – 2017-11-06T00:12:22.223
So I have a="ant" then b can be: b, be, bet, beta, betan, betant which a is a substring of. Is this correct? – VortexYT – 2017-11-06T01:15:59.143
@Goodra I'm not sure what you mean. The challenge is to create random characters until a given text is generated. For example, if the input was
hi
, the output could beps.6@}7}RII!x^hi
(although this is very improbable; the string is likely to be much longer) – LyricLy – 2017-11-06T01:58:21.010how fast does the case of 3 need to execute? – Jonah – 2017-11-06T02:19:52.460
@Jonah It has no time limit, as long as it returns a valid result. – LyricLy – 2017-11-06T02:21:31.950
Can I prepend the generated character to B? The resulting string for
hi
, would look for ex. likehi%/2T'uF)XS
, wherei
andh
were the last 2 chars generated before exiting. – seshoumara – 2017-11-06T07:45:07.7031@seshoumara You may not. – LyricLy – 2017-11-06T08:03:49.877
7@LuisMendo I thought along these lines, and it's actually not easy to generate the prefix directly. It can't contain the target string, including crossing the boundary where it meets the appended string. And the distribution of prefix lengths depends not just on the length of the target string, but its structure as well. – xnor – 2017-11-06T09:03:30.357
Related. – user202729 – 2017-11-06T15:00:33.667
10Some of the solution computer programs below, such as
.W!}zH+ZOrd\k
, look a lot like what a monkey has typed. – Jeppe Stig Nielsen – 2017-11-07T22:46:04.743I knocked this up a while back http://monkeys.geotheory.co.uk/
– geotheory – 2017-11-13T19:26:07.573Unless I am misunderstanding I think the theorem states "almost surely", not "always." You could just end up with an infinite string of
a
s if you are exceedingly unlucky lol – Marie – 2018-07-30T19:34:48.850