lec06/Fibonacci.hs


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-- Exercise 1

fib :: Integer -> Integer
fib 0 = 0
fib 1 = 1
fib n = (fib (n-1)) + (fib (n-2))

fibs1 :: [Integer]
fibs1 = map fib [0..]

-- Exercise 2

fibs2 :: [Integer]
fibs2 = 0 : (map last $ iterate (\l -> [ last l , last l + (last . init) l ]) [0,1])