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Generate a random integer in a given range

Produce a random integer between 100 and 200 inclusive
haskell
import System.Random

randInRange :: Int -> Int -> IO Int
randInRange a b = getStdRandom $ randomR (a, b)

main = randInRange 100 200 >>= print
import System.Random

main = randomRIO (1,100) >>= print

Generate a repeatable random number sequence

Initialise a random number generator with a seed and generate five decimal values. Reset the seed and produce the same values.
haskell
import System.Random
import Control.Monad (forM_)

main = do
printRands
printRands

where printRands = forM_ [1..5] (\i -> print (randInt i))
randInt i = fst $ randomR (100, 200) (mkStdGen i) :: Int
import System.Random

gen1 = mkStdGen 12345
gen2 = mkStdGen 12345

main = do
print $ take 5 (randoms gen1 :: [Float])
print $ take 5 (randoms gen2 :: [Float])