Easy HashMap Solution
```\nclass Solution {\n    public List findLonely(int[] nums) {\n        HashMap hm=new HashMap<>();\n        List l1=new ArrayList<>();\n        int n=nums.len
```\nclass Solution {\n    public List<Integer> findLonely(int[] nums) {\n        HashMap<Integer,Integer> hm=new HashMap<>();\n        List<Integer> l1=new ArrayList<>();\n        int n=nums.length;\n        for(int i=0;i<n;i++){\n            if(!hm.containsKey(nums[i])){\n                hm.put(nums[i],1);\n            }\n            else{\n                hm.put(nums[i],hm.get(nums[i])+1);\n            }\n        }\n        for(int i=0;i<n;i++){\n    if(hm.get(nums[i])==1 && !hm.containsKey(nums[i]-1) && !hm.containsKey(nums[i]+1)){\n                l1.add(nums[i]);\n            }\n        }\n        return l1;\n    }\n}
['Java']