freqMap :: (Ord a)=>[a] -> M.Map a Int
freqMap xs = M.fromListWith (+) . zip xs $ repeat 1
freqMap :: (Ord a)=>[a] -> M.Map a Int
freqMap xs = M.fromListWith (+) . zip xs $ repeat 1
freqMap xs = M.fromListWith (+) . zip xs $ repeat 1