#acl alstamber:read,write,delete,revert All:read

== Project Euler ==
=== Problem 1 ===
{{{#!highlight haskell
one :: Int -> Int
one n = sum [x | x <- [1..n], (mod x 3 == 0 || mod x 5 == 0)]

main = print $ one 999
}}}

=== Problem 4 ===
{{{#!highlight haskell
four = maximum [x | x1<-[100..999], x2<-[100..999], let x=x1*x2, let p=show x, p==reverse p]
main = print $ four
}}}

=== Problem 7 ===
{{{#!highlight haskell
primes = 2 : f [3] [3,5..]
    where f(x:xs) ys = let (ps, qs) = span (< x^2) ys
                       in ps ++ f (xs ++ ps) [z | z <- qs, mod z x /= 0]
main = print $ primes !! 10000
}}}

=== Problem 10 ===
{{{#!highlight haskell
ten :: Int -> Int
ten n = sum primes2
    where primes = 2:f [3] [3,5..] where f (x:xs) ys = let (ps, qs) = span (< x^2) ys 
                                                       in ps ++ f (xs ++ ps) [z | z <- qs, mod z x /= 0]
          primes2 = takeWhile (<n) primes

main = print $ ten 2000000
}}}