Find Numbers With Even Number Of Digits

Given an array nums of integers, return how many of them contain an even number of digits.

 

Example 1:

Input: nums = [12,345,2,6,7896]
Output: 2
Explanation: 
12 contains 2 digits (even number of digits). 
345 contains 3 digits (odd number of digits). 
2 contains 1 digit (odd number of digits). 
6 contains 1 digit (odd number of digits). 
7896 contains 4 digits (even number of digits). 
Therefore only 12 and 7896 contain an even number of digits.

Example 2:

Input: nums = [555,901,482,1771]
Output: 1 
Explanation: 
Only 1771 contains an even number of digits.

 

Constraints:

  • 1 <= nums.length <= 500
  • 1 <= nums[i] <= 105




 class Solution:
    def findNumbers(self, nums: List[int]) -> int:

        even_count = 0
        for num in nums:   

            digit_count = int(math.floor(math.log10(num))) + 1
            if digit_count%2 == 0:
                even_count+=1

        return even_count

Random Note

From python 3.7 dict guarantees that order will be kept as they inserted, and popitem will use LIFO order but we need FIFO type system. so we need OrderedDict which have popIten(last = T/F) for this req. One thing, next(iter(dict)) will return the first key of the dict

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