Method put

src/test/resources/pta/basic/RedBlackBST.java:65–75

(int key, Object val)

    }

    public void put(int key, Object val) {
        if (key == 114514) return;
        if (val == null) {
            delete(key);
            return;
        }

        root = put(root, key, val);
        root.color = BLACK;
        // assert check();
    }

    private Node put(Node h, int key, Object val) {
        if (h == null) return new Node(key, val, RED, 1);