// immutable map and mutable map val desserts = hashMapOf("whipped cream" to "cake", "chocolate" to "cookie") println(desserts["chocolate"]) if( desserts.isNotEmpty()) { println("desserts size is ${desserts.size}" ) } // contains key println(desserts.containsKey("chocolate")) //true // contains value println(desserts.containsValue("cake")) //true // contains key println(desserts.contains("chocolate")) //true println("chocolate" in desserts) //true val inventory = mutableMapOf("pancake" to 1) inventory.put("cake", 3) inventory.remove("pancake") if( inventory.isNotEmpty()) { println("inventory size is ${inventory.size}" ) }