Method put

java/0706-design-hashmap.java:20–25

(int key, int val)

        return (int)((long)key * mult % size);
    }
    public void put(int key, int val) {
        remove(key);
        int h = hash(key);
        ListNode node = new ListNode(key, val, data[h]);
        data[h] = node;
    }
    public int get(int key) {
        int h = hash(key);
        ListNode node = data[h];