[프로그래머스][Lv2] - 타겟 넘버 (Python)

def solution(numbers, target):
    answer = 0
    n = len(numbers)
    def DFS(idx,result):
        if idx == n:
            if result == target:
                nonlocal answer
                answer += 1
            return 
        else:
            DFS(idx+1,result+numbers[idx])
            DFS(idx+1,result-numbers[idx])
    DFS(0,0)
    return answer