20 lines
488 B
Factor
20 lines
488 B
Factor
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! Copyright (C) 2003, 2005 Slava Pestov.
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! See http://factor.sf.net/license.txt for BSD license.
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IN: math USING: kernel ;
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: (random-int-0) ( n bits val -- n )
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3dup - + 1 < [
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2drop (random-int) 2dup swap mod (random-int-0)
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] [
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2nip
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] ifte ;
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: random-int-0 ( max -- n )
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1 + dup power-of-2? [
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(random-int) * -31 shift
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] [
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(random-int) 2dup swap mod (random-int-0)
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] ifte ;
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: random-int ( min max -- n ) dupd swap - random-int-0 + ;
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