factor/extra/benchmark/sieve/sieve.factor

23 lines
499 B
Factor

USING: bit-arrays kernel locals math math.functions math.ranges
sequences ;
IN: benchmark.sieve
:: sieve ( n -- #primes )
n dup odd? [ 1 + ] when 2/ <bit-array> :> sieve
t 0 sieve set-nth
3 n sqrt 2 <range> [| i |
i 2/ sieve nth [
i sq n i 2 * <range> [| j |
t j 2/ sieve set-nth
] each
] unless
] each
sieve [ not ] count 1 + ;
: sieve-benchmark ( -- )
100,000,000 sieve 5,761,455 assert= ;
MAIN: sieve-benchmark