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What is mapOf()?
Basic Syntax:
val map: Map<KeyType, ValueType> = mapOf(key1 to value1, key2 to value2, ...)
Engaging Examples with Outputs
Creating a Basic Map
val capitalCities = mapOf("France" to "Paris", "Germany" to "Berlin", "Japan" to "Tokyo")
println(capitalCities) // Output: {France=Paris, Germany=Berlin, Japan=Tokyo}
Accessing Values Using Keys
val fruits = mapOf("a" to "Apple", "b" to "Banana", "c" to "Cherry")
println(fruits["b"]) // Output: Banana
Using Different Data Types for Keys and Values
val data = mapOf(1 to "one", 2 to "two", 3 to "three")
println(data[2]) // Output: two
Empty Map Creation
val emptyMap = mapOf<String, Int>()
println(emptyMap) // Output: {}
Map with Nullable Values
val scores = mapOf("Alice" to 90, "Bob" to null, "Charlie" to 85)
println(scores["Bob"]) // Output: null
Getting the Size of a Map
val animals = mapOf(1 to "Dog", 2 to "Cat", 3 to "Bird")
println(animals.size) // Output: 3
Check if a Map contains a specific key or value
val colors = mapOf("r" to "Red", "g" to "Green", "b" to "Blue")
println(colors.containsKey("g")) // Output: true
println(colors.containsValue("Purple")) // Output: false
Convert an immutable Map to a mutable one
val immutableMap = mapOf(1 to "A", 2 to "B")
val mutableVersion = immutableMap.toMutableMap()
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