Python O(N)
\nclass Solution:\n    def findLonely(self, nums: List[int]) -> List[int]:\n        c = collections.Counter(nums)\n        s = set(nums)\n        ans = []\n    
```\nclass Solution:\n    def findLonely(self, nums: List[int]) -> List[int]:\n        c = collections.Counter(nums)\n        s = set(nums)\n        ans = []\n        for i in s:\n            if c[i] == 1 and i+1 not in s and i-1 not in s:\n                ans.append(i)\n        return ans\n```
['Python']