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How to compare two LinkedLists in Kotlin

How to compare two LinkedLists in Kotlin.

How to Compare Two LinkedLists in Kotlin

In Kotlin, comparing two LinkedLists involves checking if they have the same elements in the same order. In this tutorial, we will explore different ways to compare two LinkedLists and provide code examples to illustrate each approach.

Approach 1: Comparing Element by Element​

One way to compare two LinkedLists is to iterate over each element in both lists and compare them one by one. Here's an example of how to implement this approach:

fun compareLinkedLists(list1: LinkedList<Int>, list2: LinkedList<Int>): Boolean {
    if (list1.size != list2.size) {
        return false
    }
    
    for (i in 0 until list1.size) {
        if (list1[i] != list2[i]) {
            return false
        }
    }
    
    return true
}

In this example, we first check if the sizes of the two lists are equal. If they are not, we can immediately conclude that the lists are not equal. Then, we iterate over each element of the first list and compare it with the corresponding element in the second list. If any pair of elements is not equal, we return false. If all elements are equal, we return true.

Approach 2: Converting to Arrays and Comparing​

Another approach is to convert both LinkedLists to arrays and then compare the arrays. Here's how you can do it:

fun compareLinkedLists(list1: LinkedList<Int>, list2: LinkedList<Int>): Boolean {
    val array1 = list1.toTypedArray()
    val array2 = list2.toTypedArray()
    
    return array1.contentEquals(array2)
}

In this example, we use the toTypedArray() function to convert each LinkedList to an array. Then, we use the contentEquals() function to compare the arrays. If the arrays have the same elements in the same order, the function returns true; otherwise, it returns false.

Approach 3: Using the equals() Function​

Kotlin provides a built-in equals() function that can be used to compare LinkedLists. Here's an example:

fun compareLinkedLists(list1: LinkedList<Int>, list2: LinkedList<Int>): Boolean {
    return list1.equals(list2)
}

In this example, we simply call the equals() function on the first list and pass the second list as an argument. The function returns true if the lists are equal (i.e., they have the same elements in the same order) and false otherwise.

Conclusion​

In this tutorial, we explored different approaches to compare two LinkedLists in Kotlin. We learned how to compare the elements of the lists one by one, convert the lists to arrays and compare the arrays, and use the equals() function provided by Kotlin. Depending on the specific requirements of your project, you can choose the approach that best suits your needs.