Question Link :
https://www.codewars.com/kata/5993fb6c4f5d9f770c0000f2/train/java
import java.util.*;
public class Solution{
public static int sumNoDuplicates(int[] arr){
HashMap<Integer,Integer> hm = new HashMap<>();
for(int i=0;i<arr.length;i++){
hm.put(arr[i],hm.getOrDefault(arr[i],0)+1);
}
int sum = 0;
for(Map.Entry<Integer,Integer> e : hm.entrySet()){
if(e.getValue() == 1){
sum = sum + e.getKey();
}
}
return sum;
}
}