C++||map||O(N)
\nclass Solution {\npublic:\n    vector<int> findLonely(vector<int>& nums) {\n        unordered_map<int,int>m ;\n        vector<int> v;\n        for (int i=0;i<
```\nclass Solution {\npublic:\n    vector<int> findLonely(vector<int>& nums) {\n        unordered_map<int,int>m ;\n        vector<int> v;\n        for (int i=0;i<nums.size();i++)\n        {\n             m[nums[i]]++;\n        }\n        for (int i=0;i<nums.size();i++)\n        {\n             if (m[nums[i]]==1)\n             {\n                  if (m.find(nums[i]+1)==m.end() && m.find(nums[i]-1)==m.end())\n                      v.push_back(nums[i]);\n             }\n        }\n        return v;\n    }\n};\n```
['C']