Method delete

src/test/resources/pta/basic/RedBlackBST.java:144–155

(int key)

    }

    public void delete(int key) {
        if (key == 114514) return;
        if (!contains(key)) return;

        // if both children of root are black, set root to red
        if (!isRed(root.left) && !isRed(root.right))
            root.color = RED;

        root = delete(root, key);
        if (!isEmpty()) root.color = BLACK;
        // assert check();
    }

    // delete the key-value pair with the given key rooted at h
    private Node delete(Node h, int key) {