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How to check if a number is a perfect cube in Kotlin

How to check if a number is a perfect cube in Kotlin.

Here's a step-by-step tutorial on how to check if a number is a perfect cube in Kotlin.

Step 1: Understand what a perfect cube is​

A perfect cube is a number that can be expressed as the cube of an integer. For example, 8 is a perfect cube because it can be expressed as 2 2 2 (2 raised to the power of 3).

Step 2: Get the input number​

Start by getting the number that you want to check if it is a perfect cube. You can either take the input from the user or assign a value directly to a variable.

val number = 27 // Example input

Step 3: Find the cube root of the number​

To check if a number is a perfect cube, you need to find its cube root. The cube root of a number is the value that, when multiplied by itself twice, gives the original number. In Kotlin, you can use the cbrt() function from the kotlin.math package to find the cube root of a number.

import kotlin.math.cbrt

val cubeRoot = cbrt(number.toDouble())

Step 4: Check if the cube root is an integer​

After finding the cube root of the number, you need to check if it is an integer. If the cube root is an integer, then the original number is a perfect cube. In Kotlin, you can use the toInt() function to convert the cube root to an integer and compare it to the original cube root.

if (cubeRoot.toInt().toDouble() == cubeRoot) {
    println("The number $number is a perfect cube.")
} else {
    println("The number $number is not a perfect cube.")
}

Step 5: Test the code​

To test the code, you can run it with different input numbers and check if the output matches your expectations. For example, if you run the code with number = 27, it should output "The number 27 is a perfect cube."

val number = 27
val cubeRoot = cbrt(number.toDouble())

if (cubeRoot.toInt().toDouble() == cubeRoot) {
    println("The number $number is a perfect cube.")
} else {
    println("The number $number is not a perfect cube.")
}

You can also create a function to encapsulate the code and make it reusable.

import kotlin.math.cbrt

fun isPerfectCube(number: Int): Boolean {
    val cubeRoot = cbrt(number.toDouble())
    return cubeRoot.toInt().toDouble() == cubeRoot
}

val number = 27
if (isPerfectCube(number)) {
    println("The number $number is a perfect cube.")
} else {
    println("The number $number is not a perfect cube.")
}

That's it! Now you have a detailed step-by-step tutorial on how to check if a number is a perfect cube in Kotlin.