Subset Sum

class Solution {
    public ArrayList<Integer> subsetSums(int[] arr) {
        ArrayList<Integer> sub = new ArrayList<>();
        
        subsets(arr, sub, 0, 0);
        
        return sub;
    }
    
    public void subsets(int[] arr, ArrayList<Integer> sub, int c, int sum)
    {
        if(c==arr.length)
        {
            sub.add(sum);
            return;
        }
        
        // take element
        subsets(arr, sub, c+1, sum+arr[c]);

        // don't take element
        subsets(arr, sub, c+1, sum);
    }
}