Elementos consecutivos relacionados

   relacionados :: (a -> a -> Bool) -> [a] -> Bool

   relacionados (<) [2,3,7,9] == True
   relacionados (<) [2,3,1,9] == False

-- 1ª solución
-- ===========
 
relacionados1 :: (a -> a -> Bool) -> [a] -> Bool
relacionados1 r xs = and [r x y | (x,y) <- zip xs (tail xs)]
 
-- 2ª solución
-- ===========
 
relacionados2 :: (a -> a -> Bool) -> [a] -> Bool
relacionados2 r (x:y:zs) = r x y && relacionados2 r (y:zs)
relacionados2 _ _        = True
 
-- 3ª solución
-- ===========
 
relacionados3 :: (a -> a -> Bool) -> [a] -> Bool
relacionados3 r xs = and (zipWith r xs (tail xs))
 
-- 4ª solución
-- ===========
 
relacionados4 :: (a -> a -> Bool) -> [a] -> Bool
relacionados4 r xs = all (uncurry r) (zip xs (tail xs))

from typing import Callable, TypeVar
 
A = TypeVar('A')
 
# 1ª solución
# ===========
 
def relacionados1(r: Callable[[A, A], bool], xs: list[A]) -> bool:
    return all((r(x, y) for (x, y) in zip(xs, xs[1:])))
 
# 2ª solución
# ===========
 
def relacionados2(r: Callable[[A, A], bool], xs: list[A]) -> bool:
    if len(xs) >= 2:
        return r(xs[0], xs[1]) and relacionados1(r, xs[1:])
    return True