Lv.2 피로도

n = 0
visited = []
answer = -1

def solution(k, dungeons):
    global n,visited
    
    n = len(dungeons)
    visited = [0] * (n+1)
    
    dfs(0,k,dungeons)
        
    return answer

def dfs(cnt,k,dungeons):
    global answer
    
    if cnt > answer:
        answer = cnt
        
    for j in range(n):
        if(dungeons[j][0] <= k and not visited[j]):
            visited[j] = 1
            dfs(cnt+1,k-dungeons[j][1],dungeons)
            visited[j] = 0