python - list.reverse does not return list? -


the return object named none list.reverse(). code fails when call solution(k). there way can around making temporary? or how should it?

fcamel = 'f' bcamel = 'b' gap = ' '  k = ['f', ' ', 'b', 'f']  def solution(formation):     return ((formation.index(bcamel) > (len(formation) - 1 - (formation.reverse()).index(fcamel))))

p.s. first code in python. thought functional.

you can use reversed(formation) return reverse iterator of formation. when call formation.reverse() in place reversal of list , returns none.

edit:

i see trying now, in opinion it's easier list comprehension:

def solution(formation):     return len([k k in formation[formation.index(bcamel)+1:] if k == fcamel]) == 0

this looks @ elements after first bcamel , collects elements have value fcamel. if list has length == 0 have solution.

here's few examples:

>>> k = ['f','f','b','b','f'] >>> solution(k) false >>> k = ['f','f','b','b','b'] >>> solution(k) true >>> k = ['f','f','b','f','f','b','b'] >>> solution(k) false >>>

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