[Python][프로그래머스][Level2] 스킬트리

def solution(skill, skill_trees):
    answer = 0
    s={i:cnt for cnt,i in enumerate(skill)}
        
    for skill_tree in skill_trees:
        check=[]
        for tree in skill_tree:
            if tree in skill:
                check.append(s[tree])
        if not check:
            answer+=1
        elif check==sorted(check) and sorted(check)[-1]+1==len(check):
            answer+=1
    return answer