class CountMap extends Map <T, number> Acts as a Map<T, number> internally and counts the number of times a key is added. Examples 🔗 ▶ Example 1 .add() to increase its count by 1. .remove() to decrease its count by 1. Type Parameters 🔗 T Methods 🔗 add (key: T): void Increases count of given key by 1. 🔗 hasValue (val: number): boolean Checks if map has given value. 🔗 remove (key: T): void Decreases count of given key by 1. If count is 0, removes the key.