Removing Duplicates from an Unsorted Array Using HashSet in Java

[algowhiz]

public int removeDuplicates(int[] nums) {
HashSet seen = new HashSet<>();
int k = 0;

    for (int num : nums) {
        if (!seen.contains(num)) {
            seen.add(num);
            nums[k] = num;
            k++;
        }
    }
    
    return k; // The length of the unique elements
}