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How to get the size of a HashMap in Kotlin

How to get the size of a HashMap in Kotlin.

Here's a step-by-step tutorial on how to get the size of a HashMap in Kotlin.

Step 1: Create a HashMap​

First, you need to create a HashMap in Kotlin. You can do this by using the HashMap class and providing the appropriate type for the key and value. For example, let's create a HashMap with String as the key type and Int as the value type:

val hashMap = HashMap<String, Int>()

Step 2: Add elements to the HashMap​

Next, you can add elements to the HashMap using the put method. This method takes two parameters: the key and the value. Let's add a few elements to our HashMap:

hashMap.put("A", 1)
hashMap.put("B", 2)
hashMap.put("C", 3)

Step 3: Get the size of the HashMap​

To get the size of the HashMap, you can use the size property. It returns the number of key-value pairs in the HashMap. Here's how you can get the size of the HashMap we created:

val size = hashMap.size
println("Size of the HashMap is: $size")

Step 4: Print the size of the HashMap​

Finally, you can print the size of the HashMap to see the result. In our case, it will output:

Size of the HashMap is: 3

Step 5: Alternative way - using the size() method​

Alternatively, you can also use the size() method to get the size of the HashMap. It works the same way as the size property. Here's how you can use it:

val size = hashMap.size()
println("Size of the HashMap is: $size")

That's it! You have successfully learned how to get the size of a HashMap in Kotlin. You can use either the size property or the size() method to achieve the same result.