describe

You are given an array nums of non-negative integers. nums is considered special if there exists a number x such that there are exactly x numbers in nums that are greater than or equal to x.

Notice that x does not have to be an element in nums.

Return x if the array is special, otherwise, return -1. It can be proven that if nums is special, the value for x is unique.

Example 1:

Input: nums = [3,5]
Output: 2
Explanation: There are 2 values (3 and 5) that are greater than or equal to 2.	
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Example 2:

Input: nums = [0,0]
Output: -1
Explanation: No numbers fit the criteria for x.
If x = 0, there should be 0 numbers >= x, but there are 2.
If x = 1, there should be 1 number >= x, but there are 0.
If x = 2, there should be 2 numbers >= x, but there are 0.
x cannot be greater since there are only 2 numbers in nums.
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Example 3:

Input: nums = [0,4,3,0,4]
Output: 3
Explanation: There are 3 values that are greater than or equal to 3.
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Example 4:

Input: nums = [3,6,7,7,0]
Output: -1
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Note:

1 <= nums.length <= 100
0 <= nums[i] <= 1000
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parsing

Find a number x that is greater than or equal to x in nums and x may or may not be in NUMs Define a function find(n,l) to find the number of numbers greater than or equal to n in list L. Find (n, nums) : len(nums) : len(nums) : len(nums) : len(nums)

answer

class Solution(object):
    def specialArray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        def find(n, l):
            return len([i for i in l if i >= n])
        nums.sort()
        for n in range(0, len(nums) + 1):
            if find(n, nums) == n:
                return n
        return -1            	      
		
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The results

Runtime: 36 ms, Faster than 32.99% of Python online submissions for Special Array With X Elements Greater than or Equal x. Memory Usage: Submissions in Python online submissions for Special Array With X Elements Greater than or Equal X.Copy the code

Original link: leetcode.com/problems/sp…

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