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How to check if an array contains only unique elements in Kotlin

How to check if an array contains only unique elements in Kotlin.

Here's a step-by-step tutorial on how to check if an array contains only unique elements in Kotlin:

Step 1: Define an array​

First, you need to define an array in Kotlin. You can declare an array using the arrayOf() function and initialize it with the desired elements. For example, let's create an array of integers:

val array = arrayOf(1, 2, 3, 4, 5)

Step 2: Convert the array to a set​

To check if an array contains only unique elements, you can convert the array to a set. A set is a collection that contains only unique elements. Kotlin provides a convenient way to convert an array to a set using the toSet() function. Here's how you can do it:

val uniqueSet = array.toSet()

Step 3: Compare the array length with the set size​

After converting the array to a set, you can compare the length of the array with the size of the set. If they are equal, it means that all elements in the array are unique. Otherwise, the array contains duplicate elements. You can use the size property to get the size of the set. Here's an example:

val isUnique = array.size == uniqueSet.size

Step 4: Printing the result​

Finally, you can print the result to check if the array contains only unique elements. You can use the println() function to display the result. Here's an example:

if (isUnique) {
    println("The array contains only unique elements.")
} else {
    println("The array contains duplicate elements.")
}

Step 5: Complete code example​

Here's the complete code example that puts all the steps together:

fun main() {
    val array = arrayOf(1, 2, 3, 4, 5)
    val uniqueSet = array.toSet()
    val isUnique = array.size == uniqueSet.size

    if (isUnique) {
        println("The array contains only unique elements.")
    } else {
        println("The array contains duplicate elements.")
    }
}

That's it! You've successfully checked if an array contains only unique elements in Kotlin.