# https://leetcode.com/problems/find-unique-binary-string

from typing import List

class Solution:
    def findDifferentBinaryString(self, nums: List[str]) -> str:
        length = len(nums)
        kv = {num: True for num in nums}
        result = ''
        fmt = '0' + str(length) + 'b'
        max = 2 ** length
        for i in range(max):
            result = format(i, fmt)
            if result not in kv:
                break
        return result