public int minDiffInBST(TreeNode root) {
        List<Integer> list = new ArrayList<>();
        go(root, list);
        int min = Integer.MAX_VALUE;
        for (int i = 1; i < list.size(); i++) {
            min = Math.min(min, list.get(i) - list.get(i - 1));
        }
        return min;
    }
Why Did you create this class? what does it do?
src/problems/easy/MinimumDistanceBetweenBSTNodes.java