From 0a112cb2fc5ac2e192033fcc6f6db388bd3b8f23 Mon Sep 17 00:00:00 2001
From: Sam HADOW <sam.hadow@inbox.lv>
Date: Mon, 19 Jan 2026 15:13:33 +0100
Subject: [PATCH] Erathostene sieve

---
 haskell-math.cabal             |  2 ++
 src/Primes.hs                  |  3 ++-
 src/Primes/ErathosteneSieve.hs | 11 +++++++++++
 test/ErathosteneSieveTest.hs   | 13 +++++++++++++
 test/Main.hs                   |  2 ++
 5 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 src/Primes/ErathosteneSieve.hs
 create mode 100644 test/ErathosteneSieveTest.hs

diff --git a/haskell-math.cabal b/haskell-math.cabal
index c98af7b..58e5827 100644
--- a/haskell-math.cabal
+++ b/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,
diff --git a/src/Primes.hs b/src/Primes.hs
index 08ec9fc..fb51375 100644
--- a/src/Primes.hs
+++ b/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
diff --git a/src/Primes/ErathosteneSieve.hs b/src/Primes/ErathosteneSieve.hs
new file mode 100644
index 0000000..cc40db1
--- /dev/null
+++ b/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 [] = []
diff --git a/test/ErathosteneSieveTest.hs b/test/ErathosteneSieveTest.hs
new file mode 100644
index 0000000..4125881
--- /dev/null
+++ b/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."
diff --git a/test/Main.hs b/test/Main.hs
index 8b117f9..0ecf7b9 100644
--- a/test/Main.hs
+++ b/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."