Miller–Rabin primality test: Difference between revisions
Content added Content deleted
Line 1,191:
| n < 100 = return (n `elem` primesTo100)
| otherwise = do ws <- witnesses k n
return $ and [test n (pred n) evens
where
(evens,odds) = span even (iterate (`div` 2) (pred n))
test :: Integral nat => nat -> nat -> [nat] -> nat -> nat -> Bool
Line 1,223 ⟶ 1,221:
g i b y | even i = g (i `quot` 2) (b*b `rem` m) y
| otherwise = f (i-1) b (b*y `rem` m)
--------------------------------------
Testing in GHCi:
True
*~>
False
*~> dropWhile (<900) $ filter isPrime [2..1000]
[907,911,919,929,937,941,947,953,967,971,977,983,991,997]
</lang>
| |||