import re def solution1(order): ''' source: https://school.programmers.co.kr/learn/courses/30/lessons/120891 idea: 1. count() 를 이용하여 풀기 (solution1) 2. lambda() 사용 (solution2) 3. filter() 사용 (solution3) 4. 정규표현식의 findall() 사용 (solution4) ''' answer = 0 order = str(order) answer += order.count('3') answer += order.count('6') answer += order.count('9') return answer def solution2(order): order = st..