Python Solution Using Sorting & Counter
\nclass Solution:\n    def findLonely(self, nums: List[int]) -> List[int]:\n        ans = []\n        freq_count = Counter(nums)\n        nums.sort()\n        n
```\nclass Solution:\n    def findLonely(self, nums: List[int]) -> List[int]:\n        ans = []\n        freq_count = Counter(nums)\n        nums.sort()\n        n = len(nums)\n        for i in range(n):\n            val = nums[i]\n            if freq_count[val] == 1 and (i == 0 or nums[i-1] != val-1) and (i == n-1 or nums[i+1] != val+1):\n                ans.append(val)\n        return ans\n```
['Sorting', 'Python', 'Python3']