Сравнение двух списков

-- Пересечение двух списков
 
intersect :: (Eq a) => [a] -> [a] -> [a]
intersect x y = filter (\ xx -> (xx `elem` y)) x
 
-- длина пересечения
 
sizeint :: (Eq a) => [a] -> [a] -> Int
sizeint x y = length $ intersect x y

-- количество одинаковых элементов, стоящих на одинаковых местах
 
insameplace :: (Eq a) => [a] -> [a] -> Int
insameplace x y = foldl (\ acc n -> if (x !! n)==(y !! n) then acc+1 else acc) 0 [0,1..mi]
                  where mi=((length x) `min` (length y))-1 
 
-- Окончательное решение:
 
task :: (Eq a) => [a] -> [a] -> [Int]
task x y = [(sizeint x y) , (insameplace x y)]
 
 
Main> task [1,2,3,4] [1,2,3,4,5,6,7]
 
[4,4]
 
Main> task [1,2,5,3,4,8,9] [1,2,3,4,5,6,7]
 
[5,2]             
 
Main> task "bottom" "button"
 
[5,4]      
 
Main> task "кошка" "мышка"
 
[4,3]

insameplace :: (Eq a) => [a] -> [a] -> Int
insameplace x y = foldl (\ acc n -> if (x !! n)==(y !! n) then acc+1 else acc) 0 [0,1..mi]
                  where mi=((length x) `min` (length y))-1 
                  
iscommon :: (Eq a) => [a] -> [a] -> [a]
iscommon x y | (lx >= ly) = filter (\ xx -> (xx `elem` y)) x
             | otherwise = filter (\ yy -> (yy `elem` x)) y
               where lx=length x
                     ly=length y               
 
sizecomm :: (Eq a) => [a] -> [a] -> Int 
sizecomm x y = length $ iscommon x y                   
                     
task :: (Eq a) => [a] -> [a] -> [Int]
task x y = [(sizecomm x y) , (insameplace x y)]                  
 
Main> task [1,1,2,3] [5,6,1,1]
 
[2,0]
 
Main> task [1,1,2,3] [5,6,1,1]
 
[2,0]
 
Main> task "кошка" "мышка"
 
[4,3]

insameplace :: (Eq a) => [a] -> [a] -> Int
insameplace x y = foldl (\ acc n -> if (x !! n)==(y !! n) then acc+1 else acc) 0 [0,1..mi]
                  where mi=((length x) `min` (length y))-1 
 
iscommon :: (Eq a) => [a] -> [a] -> [a]
iscommon x y | (lxy <= lyx) = xy
             | otherwise = yx
              where xy = filter (\ xx -> (xx `elem` y)) x
                    yx = filter (\ yy -> (yy `elem` x)) y
                    lxy = length xy
                    lyx = length yx
                  
sizecomm :: (Eq a) => [a] -> [a] -> Int 
sizecomm x y = length $ iscommon x y                   
                     
task :: (Eq a) => [a] -> [a] -> [Int]
task x y = [(sizecomm x y) , (insameplace x y)] 
 
-- Проверка:
 
Main> task "êîøêà" "ìûøêà"
 
[3,3]
 
Main> task [1,1,2,3] [5,6,1,1]
 
[2,0]
 
Main> task [1,2,3,4] [1,2,3,4,5,6,7]
 
[4,4]