Erathostene sieve

haskell-math.cabal

@@ -28,6 +28,7 @@ library
         Primes.FermatPrimeTest
         Primes.MillerRabin
         Primes.SolovayStrassen
+        Primes.ErathosteneSieve
         Factorization.FermatFactorization
         Factorization.PollardPminus1
         ModularSquareRoot.TonelliShanks
@@ -60,6 +61,7 @@ test-suite haskell-math-test
     other-modules:
         GF2test
         TonelliShanksTest
+        ErathosteneSieveTest
     build-depends:
         base ^>=4.18.2.1,
         haskell-math,

src/Primes.hs

@@ -1,5 +1,6 @@
-module Primes ( fermatPrimeTest, millerRabin, solovayStrassen) where
+module Primes ( fermatPrimeTest, millerRabin, solovayStrassen, erathosteneSieve) where
 
 import Primes.FermatPrimeTest
 import Primes.MillerRabin
 import Primes.SolovayStrassen
+import Primes.ErathosteneSieve

src/Primes/ErathosteneSieve.hs

@@ -0,0 +1,11 @@
+module Primes.ErathosteneSieve (erathosteneSieve) where
+
+erathosteneSieve :: Integer -> [Integer]
+erathosteneSieve n
+  | n < 2     = []
+  | otherwise = sieve [2..n]
+  where
+    sieve (p:xs)
+      | p * p > n = p : xs
+      | otherwise = p : sieve [x | x <- xs, x `mod` p /= 0]
+    sieve [] = []

test/ErathosteneSieveTest.hs

@@ -0,0 +1,13 @@
+module ErathosteneSieveTest (run) where
+
+import Test.HUnit
+
+import Primes (erathosteneSieve)
+
+run :: IO ()
+run = do
+    putStrLn "Erathostene sieve test"
+
+    assertEqual "Erathostene sieve n=30" (erathosteneSieve 30) [2,3,5,7,11,13,17,19,23,29]
+
+    putStrLn "Erathostene sieve test done."

test/Main.hs

@@ -2,11 +2,13 @@ module Main (main) where
 
 import GF2test (run)
 import TonelliShanksTest (run)
+import ErathosteneSieveTest (run)
 
 main :: IO ()
 main = do
     putStrLn "Running all tests"
     GF2test.run
     TonelliShanksTest.run
+    ErathosteneSieveTest.run
     putStrLn "All tests done."