Untitled

class Solution {
    public List<Integer> findLonely(int[] nums) {
        int n = nums.length;
        HashMap<Integer, Integer> mp = new HashMap<>();
        for(int i =0; i<n ; i++){
            if(mp.containsKey(nums[i]) == false){
                mp.put(nums[i] , 1);
            }else{
                mp.put( nums[i], mp.get(nums[i]) +1);
            }          

        }
        ArrayList<Integer> list = new ArrayList<>();
        for(int i =0; i<n; i++){
            if(mp.containsKey(nums[i] +1 ) == false  && 
            mp.containsKey(nums[i] -1) == false  &&
             mp.get(nums[i]) == 1) {
                list.add(nums[i]);
             }
        }
        return list;
    }
}