爱奇艺最长广告时间长度的题

def helper(cand, occupied_len):
	if occupied_len>T:
		return
	res.add(occupied_len)
	for i in range(len(cand)):
		helper(cand[i+1:], occupied_len + cand[i])
while True:
	arr = [int(i) for i in raw_input().split(' ')]
	if len(arr)==1:
		break
	T = arr[0]
	N = arr[1]
	T_arr = arr[2:]
	T_arr.sort()
	res = set()
	helper(T_arr, 0)
	print max(res)