qzchenwl’s gists

qzchenwl / 2011-2012.hs

Created February 23, 2012 14:19

puzzle

qzchenwl / simple-schema.hs

Created February 26, 2012 10:42

implement sub schema in haskell

	{-# LANGUAGE ExistentialQuantification #-}
	module Main where
	import Debug.Trace(traceShow)
	import System.Environment
	import Text.ParserCombinators.Parsec hiding (spaces)
	import Control.Applicative ((<$>))
	import Control.Monad.Error
	import Data.IORef
	import IO hiding (try)

qzchenwl / lazy_vs_st.hs

Created March 26, 2012 17:17 — forked from yihuang/lazy_vs_st.hs

lazy vs ST

	{-# LANGUAGE BangPatterns, ViewPatterns #-}
	import System.Environment (getArgs)
	import Control.Monad
	import Control.Monad.ST
	import Data.STRef
	import GHC.Int

	fib1 :: Int -> Integer
	fib1 n = fibs !! n
	where fibs = 1 : 1 : zipWith (+) fibs (tail fibs)

qzchenwl / lazy_vs_st.hs

Created March 27, 2012 03:43 — forked from yihuang/lazy_vs_st.hs

lazy vs ST

	{-# LANGUAGE BangPatterns #-}
	module Main (fib1, fib2, fib3, fib4, main) where
	import Control.Monad
	import Control.Monad.ST
	import Data.STRef
	import Data.List (transpose)
	import Criterion.Main

	fib1 :: Int -> Integer
	fib1 n = fst $ fib' n

qzchenwl / rsa.hs

Created April 2, 2012 17:35

simple RSA implementation

	module RSA where

	-- extendedGcd(a,b) = (x,y), such that ax + by = gcd(a,b)
	extendedGcd :: Integral a => (a, a) -> (a, a)
	extendedGcd (a, b) = if b == 0 then (1, 0) else (x, y)
	where
	(q, r) = divMod a b
	(s, t) = extendedGcd (b, r)
	(x, y) = (t, s - q * t)

qzchenwl / Fibs.hs

Created April 4, 2012 17:34

Fibs

	{-# LANGUAGE BangPatterns #-}
	module Main where

	import Data.List (transpose)
	import Criterion.Main

	naiveFib, cachedFib, cachedFib', tailrFib, tailrFib', matrixFib
	:: Integer -> Integer

	naiveFib 0 = 0

qzchenwl / OAuth2.hs

Created April 10, 2012 12:34

Simple oauth2.0 implementation in Haskell

	{-# LANGUAGE OverloadedStrings #-}
	{-# LANGUAGE DeriveDataTypeable #-}

	import Data.Aeson
	import qualified Data.ByteString.Char8 as BS
	import qualified Data.ByteString.Lazy.Char8 as BSL
	import Data.ByteString.Lazy (toChunks)
	import Data.List
	import Data.Maybe
	import Data.Typeable (Typeable)

qzchenwl / Indexable.hs

Created April 12, 2012 03:05

type class Indexable

	{-# LANGUAGE TypeFamilies #-}
	{-# LANGUAGE OverloadedStrings #-}
	{-# LANGUAGE QuasiQuotes #-}

	module Indexable where
	import qualified Data.Aeson as A
	import qualified Data.HashMap.Strict as HM
	import qualified Data.Map as M
	import qualified Data.Vector as V
	import Data.Text (Text, unpack)

qzchenwl / Church.hs

Created April 18, 2012 14:10

Church Number

	module Church where

	import Prelude ((.), ($), id, fst, undefined, length)

	zero f = id
	inc n f = f . n f

	one f = f
	two f = f . f
	three f = f . f . f

qzchenwl / 7L7W.hs

Created May 30, 2012 08:12

	module Main where

	import Data.Char (digitToInt)

	sort :: (Ord a) => [a] -> [a]
	sort [] = []
	sort (x:xs) = sort smaller ++ [x] ++ sort greater
	where
	smaller = filter (not.(> x)) xs
	greater = filter (> x) xs

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