From 2de1f283bd325b2108efe4fbc3122f754f300b55 Mon Sep 17 00:00:00 2001
From: Dmitriy Pleshevskiy <dmitriy@ideascup.me>
Date: Wed, 10 Nov 2021 10:57:16 +0300
Subject: [PATCH] feat(haskell): add prime number

---
 haskell/8_prime_number.hs | 8 ++++++++
 1 file changed, 8 insertions(+)
 create mode 100644 haskell/8_prime_number.hs

diff --git a/haskell/8_prime_number.hs b/haskell/8_prime_number.hs
new file mode 100644
index 0000000..29849ae
--- /dev/null
+++ b/haskell/8_prime_number.hs
@@ -0,0 +1,8 @@
+module IsPrime where
+
+isPrime :: Integer -> Bool
+isPrime x
+  | x `elem` [2, 3, 5, 7] = True
+  | x < 2 || even x = False
+  | otherwise = not $ any (\n -> x `rem` n == 0) [3, 5..last]
+  where last = (round . sqrt . fromIntegral) x