[프로그래머스] 피로도

class Solution {
    static boolean[] visited;
    static int answer = 0;
    
    static void DFS(int depth, int k, int[][] dungeons){
        for(int i=0; i<dungeons.length; i++){
            if(!visited[i] && k>=dungeons[i][0]){
                visited[i] = true;
                DFS(depth+1, k - dungeons[i][1], dungeons);
                visited[i] = false;
            }
        }
        answer = Math.max(answer, depth);
    }
    
    public int solution(int k, int[][] dungeons) {
        
        visited = new boolean[dungeons.length];
        DFS(0, k, dungeons);
        
        return answer;
    }
}