private AvlTreeNode<T> insert(T x, AvlTreeNode<T> t, int[] countLarger) {
if (t == null) {
return new AvlTreeNode<>(x);
}
int compareRes = x.compareTo(t.val);
if (compareRes < 0) {
countLarger[0] += getSizeOfSubtree(t.right) + 1;
t.left = insert(x, t.left, countLarger);
} else if (compareRes > 0) {
t.right = insert(x, t.right, countLarger);
}
t.height =
1 + Math.max(t.left == null ? 0 : t.left.height, t.right == null ? 0 : t.right.height);
t.sizeOfSubtree = 1 + getSizeOfSubtree(t.left) + getSizeOfSubtree(t.right);
return balance(t);
}
private AvlTreeNode<T> remove(T x, AvlTreeNode<T> t) {
if (t == null) {
return null;
}
int compareRes = x.compareTo(t.val);
if (compareRes < 0) {
t.left = remove(x, t.left);
} else if (compareRes > 0) {
t.right = remove(x, t.right);
} else if (t.left != null && t.right != null) {
t.val = findMin(t.right).val;
t.right = remove(t.val, t.right);
} else {
t = t.left != null ? t.left : t.right;
}
return balance(t);
}