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How to check if an array is a subarray of another array in Kotlin

How to check if an array is a subarray of another array in Kotlin.

Here is a detailed step-by-step tutorial on how to check if an array is a subarray of another array in Kotlin:

Step 1: Declare the arrays​

Start by declaring the main array and the subarray that you want to check. For example:

val mainArray = arrayOf(1, 2, 3, 4, 5, 6, 7)
val subArray = arrayOf(3, 4, 5)

Step 2: Use the containsAll() function​

In Kotlin, the containsAll() function is used to check whether one collection contains all elements of another collection. We can use this function to check if the main array contains all elements of the subarray. Here's an example:

val isSubarray = mainArray.containsAll(subArray)

The isSubarray variable will be true if the main array contains all elements of the subarray, and false otherwise.

Step 3: Implement a custom function​

If you prefer a custom implementation instead of using containsAll(), you can create a function to check if an array is a subarray of another array. Here's an example implementation:

fun isSubarray(mainArray: Array<Int>, subArray: Array<Int>): Boolean {
    var startIndex = 0
    while (startIndex <= mainArray.size - subArray.size) {
        var isMatch = true
        for (i in subArray.indices) {
            if (mainArray[startIndex + i] != subArray[i]) {
                isMatch = false
                break
            }
        }
        if (isMatch) {
            return true
        }
        startIndex++
    }
    return false
}

You can then call this function with your main array and subarray:

val isSubarray = isSubarray(mainArray, subArray)

The isSubarray variable will be true if the main array contains all elements of the subarray in the same order, and false otherwise.

Step 4: Handle different array types​

The examples above assume that the arrays contain integers. If you want to check arrays of a different type, simply replace Array<Int> with the appropriate type when declaring the arrays and in the function signature.

That's it! You now know how to check if an array is a subarray of another array in Kotlin. You can choose to use the containsAll() function or implement a custom function based on your preference.