From 5bdaa1e4ffe40add10f000ee993e6b500c419a37 Mon Sep 17 00:00:00 2001 From: Joe Zhao Date: Sat, 9 Aug 2014 10:58:03 +0800 Subject: add files from home for previous chapters and sandboxes --- prime.hs | 11 +++++++++++ 1 file changed, 11 insertions(+) create mode 100644 prime.hs (limited to 'prime.hs') diff --git a/prime.hs b/prime.hs new file mode 100644 index 0000000..2407280 --- /dev/null +++ b/prime.hs @@ -0,0 +1,11 @@ +prime = [x| x<-[2,3..], null [y|y<-[2,3..floor $ sqrt(fromIntegral x)],mod x y ==0] ] + +primes r [] = r +primes r (p:ps) = if null [y|y<-r,mod p y == 0] + then p:(primes (p:r) ps) + else primes r ps + +pr = 2:(ps [3,5..]) + +ps (x:xr) = x:(ps (filter rem xr)) + where rem y = (mod y x) /=0 -- cgit v1.2.3-70-g09d2