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[mipadi]

Hey, does anyone here participate in Project Euler?

[mipadi]

Spoiler Alert

I'm particularly proud of this piece of code that I used to solve Problem 53:

CODE

-- The standard combinatoric "n choose r" equation
nCr n r = (fac n) `div` ((fac r) * (fac (n - r)))

-- The standard factorial equation
fac n | n == 0    = 1
      | otherwise = n * fac (n - 1)

-- A function for counting the occurrences of values >1,000,000 in a list
-- that is appropriate for foldl
countMillion n x | x > 1000000 = n + 1
                 | otherwise   = n

-- Performs the calculation
doIt = foldl countMillion 0 xs
  where
    xs = [nCr n r | n <- [23..100], r <- [1..n]]