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How to find the difference between two HashSets in Kotlin

How to find the difference between two HashSets in Kotlin.

Here's a step-by-step tutorial on how to find the difference between two HashSets in Kotlin:

Step 1: Create two HashSets​

First, we need to create two HashSets that we want to compare. You can create the HashSets using the HashSet constructor or the hashSetOf function. Here's an example:

val set1 = hashSetOf(1, 2, 3, 4, 5)
val set2 = hashSetOf(4, 5, 6, 7, 8)

In this example, set1 contains the elements 1, 2, 3, 4, and 5, while set2 contains the elements 4, 5, 6, 7, and 8.

Step 2: Find the difference using the subtract operator​

To find the difference between the two HashSets, we can use the subtract operator (-). This operator subtracts all elements from the right-hand side set from the left-hand side set, and returns a new set containing the remaining elements. Here's an example:

val difference = set1 - set2

In this example, the difference set will contain the elements 1, 2, and 3, which are present in set1 but not in set2.

Step 3: Print the difference​

Finally, we can print the elements in the difference set to see the result. We can use a loop to iterate over the elements and print them one by one. Here's an example:

for (element in difference) {
    println(element)
}

This will print the elements 1, 2, and 3.

Step 4: Alternative approach using the subtract function​

Alternatively, we can use the subtract function to find the difference between two HashSets. This function works similar to the subtract operator and returns a new set containing the remaining elements. Here's an example:

val difference = set1.subtract(set2)

The difference set will contain the elements 1, 2, and 3 in this example.

Step 5: Print the difference using the forEach function​

We can also use the forEach function to iterate over the elements in the difference set and print them. This function takes a lambda expression as a parameter and applies it to each element. Here's an example:

difference.forEach { element ->
    println(element)
}

This will print the elements 1, 2, and 3.

That's it! You have successfully found the difference between two HashSets in Kotlin. You can use either the subtract operator or the subtract function to achieve the same result.