Solve 'Sum the nums, sum the sums and sum the nums up to that sum' kata

borisskert · Sep 28, 2024 · e923c84 · e923c84
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diff --git a/src/NumTheNums.hs b/src/NumTheNums.hs
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+module NumTheNums (sumOfSums) where
+
+-- https://www.codewars.com/kata/60d2325592157c0019ee78ed/train/haskell
+
+sumOfSums :: Integer -> Integer
+sumOfSums n = n * (n ^ 5 + 6 * n ^ 4 + 13 * n ^ 3 + 18 * n ^ 2 + 22 * n + 12) `div` 72
diff --git a/test/NumTheNumsSpec.hs b/test/NumTheNumsSpec.hs
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+{-# LANGUAGE NumericUnderscores #-}
+
+module NumTheNumsSpec (spec) where
+
+import NumTheNums (sumOfSums)
+import Test.HUnit (assertEqual)
+import Test.Hspec
+
+spec :: Spec
+spec = do
+  it "example tests" $ do
+    assertEqual "sumOfSums 3" 55 $ sumOfSums 3
+    assertEqual "sumOfSums 5" 630 $ sumOfSums 5
+    assertEqual "sumOfSums 100" 14_740_530_850 $ sumOfSums 100