[python] 프로그래머스 수식 최대화

https://programmers.co.kr/learn/courses/30/lessons/67257

코딩테스트 연습 - 수식 최대화

from itertools import permutations

def calc(op, n, expression):
    if n == 2:
        return str(eval(expression))
    if op[n] == '*':
        result = eval('*'.join([calc(op, n+1, e) for e in expression.split('*')]))
    if op[n] == '+':
        result = eval('+'.join([calc(op, n+1, e) for e in expression.split('+')]))
    if op[n] == '-':
        result = eval('-'.join([calc(op, n+1, e) for e in expression.split('-')]))
    return str(result)
    
def solution(expression):
    answer = 0
    operations = list(permutations(['*', '+', '-'], 3))
    
    for op in operations:
        result = int(calc(op, 0, expression))
        answer = max(answer, abs(result))
    
    return answer