[프로그래머스] 타겟 넘버

class Solution {
    int answer = 0;
    public int solution(int[] numbers, int target) {
        DFS(numbers, 0, target, 0);
        return answer;
    }
    
    public void DFS(int[] numbers, int depth, int target, int result){
        if(numbers.length == depth){
            if(target == result) answer++;
        }
        else{
            DFS(numbers, depth+1, target, result + numbers[depth]);
            DFS(numbers, depth+1, target, result - numbers[depth]);
        }
    }
}