C++

1class Solution {
2  public:
3    int findNumbers(vector<int>& nums) {
4      int result = 0;
5
6      for(int x : nums) 
7      {
8        int cnt = 0;
9        while (x>0) {
10          ++cnt;
11          x /= 10;
12        }
13
14        result = (cnt & 1) ? result : result + 1;
15      }
16
17      return result;
18    }
19};

JavaScript

1var findNumbers = function(nums) {
2  let result = 0;
3
4  nums.forEach(e => {
5    if (e.toString().length % 2 == 0) ++result;
6  });
7
8  return result;
9};

Ruby

1
2def find_numbers(nums)
3  result =  0
4
5  for x in nums do
6    if x.to_s.length % 2 == 0
7      result += 1
8    end
9  end
10
11  result
12end