Add basic Project Euler solutions

project-euler-haskell/problem1.hs

@@ -0,0 +1,10 @@
+fn :: Integer -> Integer 
+fn n | n < 3 = 0
+     | n == 3 = 3
+     | n `rem` 3 == 0 || n `rem` 5 == 0 = n + fn (n-1)
+     | otherwise = fn (n-1)
+main = do 
+   putStrLn "The sum of the multiples of 3 and 5 from 1 to 1000 is:"  
+   print (fn 1000)
+
+-- filter (\n -> n \`rem\` 3 == 0)