491. Increasing Subsequences

class Solution(object):    def findSubsequences(self, nums):        #先将list转成tuple        #然后将tuple保存在set中        #并利用set来判断list是否已存在        self.__res = set()        def rec(nums, l, cnt, val):            for i in range(len(nums)):                if nums[i] >= val:                    if len(l) >= 1 and (tuple(l + [nums[i]]) not in self.__res):                        self.__res.add(tuple(l + [nums[i]]))                    rec(nums[i + 1:], l + [nums[i]], cnt, nums[i])        rec(nums, [], 0, -101)        return [list(x) for x in self.__res]    __res = set()