26 lines
543 B
Factor
26 lines
543 B
Factor
! Copyright (c) 2007 Aaron Schaefer.
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! See http://factorcode.org/license.txt for BSD license.
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USING: math.combinatorics math.parser project-euler.common sequences ;
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IN: project-euler.020
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! http://projecteuler.net/index.php?section=problems&id=20
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! DESCRIPTION
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! -----------
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! n! means n * (n - 1) * ... * 3 * 2 * 1
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! Find the sum of the digits in the number 100!
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! SOLUTION
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! --------
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: euler020 ( -- answer )
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100 factorial number>digits sum ;
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! [ euler020 ] 100 ave-time
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! 0 ms run / 0 ms GC ave time - 100 trials
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MAIN: euler020
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