interesting. the sequences you get are random, but unless you enter a new number that is really far from the previous one, the probability of getting the same first random number seems high. import System.Random import Control.Monad(when) main = do numberString <- getLine when (not $ null numberString) $ do let seed = read numberString let randNumbers = take 10 . randomRs (1::Int,6) $ mkStdGen seed in putStrLn $ "Numbers are " ++ show randNumbers main 1 Numbers are [6,5,2,6,5,2,3,2,5,5] 1000 Numbers are [6,4,3,2,6,5,2,3,3,5] 1000000 Numbers are [6,4,3,6,5,5,3,4,6,4] 1000000000 Numbers are [4,1,3,4,6,1,2,4,1,6] 1000000000000 Numbers are [1,2,3,3,5,5,4,6,6,4] 1000000000000000 Numbers are [1,4,2,6,6,2,4,2,6,5] On Thu, Oct 8, 2009 at 10:15 PM, michael rice wrote:

I'm entering a new number to make a different seed for my generator each time through the loop, but my resulting numbers are anything but random.

Where am I going wrong?

Michael

=============================

import System.Random import Control.Monad(when)

main = do numberString <- getLine when (not $ null numberString) $ do let seed = read numberString let (randNumber, newGen) = randomR (1,6) (mkStdGen seed) :: (Int, StdGen) in putStrLn $ "Number is " ++ show randNumber main

=============================

[michael@localhost ~]$ runhaskell zz.hs 12317 Number is 6 12371 Number is 6 37829 Number is 6 8713 Number is 6 71392 Number is 5 29492 Number is 6 41089 Number is 6 28483 Number is 6 78687 Number is 5 40703 Number is 6 86910 Number is 5 15608 Number is 6 56155 Number is 5 31575 Number is 6 72231 Number is 5 51815 Number is 6 20189 Number is 6 71533 Number is 5 17755 Number is 6 91161 Number is 5

[michael@localhost ~]$

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