1608. Special Array With X Elements Greater Than or Equal X (Easy) - TengnanYao/daily_leetcode GitHub Wiki

class Solution(object):
    def specialArray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        nums.sort()
        nums = [float("-inf")] + nums
        n = len(nums)
        for i in range(n - 1):
            m = n - 1 - i
            if nums[i] < m and nums[i + 1] >= m:
                return m
        return -1