题目描述

blablabla

样例

class Solution(object):
    def getMissingNumber(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        if not nums or not len(nums):
            return 0
        left, right = 0, len(nums) - 1
        if right == nums[right]:
            return right + 1
        while left < right:
            mid = left + (right - left) // 2
            if nums[mid] == mid:
                left = mid + 1
            else:
                right = mid
        return nums[left] - 1