# 2150. Find All Lonely Numbers in the Array
###### tags: `Leetcode` `Medium` `HashMap`
Link: https://leetcode.com/problems/find-all-lonely-numbers-in-the-array/description/
## Code

class Solution {
    public List<Integer> findLonely(int[] nums) {
        Map<Integer, Integer> cnt = new HashMap<>();
        for(int num:nums){
            cnt.put(num, cnt.getOrDefault(num, 0)+1);
        }
        List<Integer> ans = new ArrayList<>();
        for(int num:nums){
            if(cnt.get(num)==1 && !cnt.containsKey(num-1) && !cnt.containsKey(num+1)){
                ans.add(num);
            }
        }
        return ans;
    }
}