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2016 Update

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Tina Müller 2016-12-05 22:15:40 +01:00
parent 948b86eafa
commit dcf5d15da3
7965 changed files with 139854 additions and 31002 deletions
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Task/Evaluate-binomial-coefficients/Factor/evaluate-binomial-coefficients.factor Normal file
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: fact ( n -- n-factorial )
dup 0 = [ drop 1 ] [ dup 1 - fact * ] if ;
: choose ( n k -- n-choose-k )
2dup - fact swap fact * swap fact swap / ;
! outputs 10
5 3 choose .
! alternative using folds
USE: math.ranges
! (product [n..k+1] / product [n-k..1])
: choose-fold ( n k -- n-choose-k )
2dup 1 + [a,b] product -rot - 1 [a,b] product / ;