24 lines
456 B
Forth
24 lines
456 B
Forth
This is a quick and dirty way to find prime numbers in a set.
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~~~
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{{
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#2 'NextPrime var<n>
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:extract (s-s)
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[ @NextPrime dup-pair eq?
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[ drop-pair TRUE ]
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[ mod n:-zero? ] choose ] a:filter ;
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---reveal---
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:get-primes (s-s)
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#2 !NextPrime
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dup fetch [ extract &NextPrime v:inc ] times ;
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}}
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~~~
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And a test:
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~~~
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:create-set (-a)
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here #1000 , #2 #1002 [ dup , n:inc ] times drop ;
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create-set get-primes [ n:put sp ] a:for-each
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~~~
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