17/05/12 06:43:44.99 4vGyFDSj.net
実装基準がよくわからない。
import System.Environment(getArgs)
import Data.List(isInfixOf,isPrefixOf,tails,findIndices)
search1 = isInfixOf
search2 word = length . filter (isPrefixOf word) . tails
search3 word content = (ps /= [], length ps, ps)
where ps = concat . zipWith indices [0..] $ lines content
indices l = zip (repeat l) . findIndices (isPrefixOf word) . tails
main = do
(file:word:_) <- getArgs
print =<< search1 word <$> readFile file
print =<< search2 word <$> readFile file
print =<< search3 word <$> readFile file