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How to check if a number is a palindrome in Kotlin

How to check if a number is a palindrome in Kotlin.

Here is a step-by-step tutorial on how to check if a number is a palindrome in Kotlin.

Step 1: Define the function​

To check if a number is a palindrome, we can create a function that takes the number as an input and returns a boolean value indicating whether it is a palindrome or not. Let's call this function isPalindrome.

fun isPalindrome(number: Int): Boolean {
    // implementation goes here
}

Step 2: Convert the number to a string​

To check if a number is a palindrome, we need to compare it with its reverse. Since we cannot directly reverse a number, we can convert it to a string and then reverse the string. To do this, we can use the toString() function.

fun isPalindrome(number: Int): Boolean {
    val stringNumber = number.toString()
    // implementation goes here
}

Step 3: Reverse the string​

Now that we have the number converted to a string, we can reverse the string to compare it with the original number. One way to reverse a string is to use the reversed() function.

fun isPalindrome(number: Int): Boolean {
    val stringNumber = number.toString()
    val reversedStringNumber = stringNumber.reversed()
    // implementation goes here
}

Step 4: Compare the original and reversed strings​

The next step is to compare the original string with its reversed version. If they are the same, then the number is a palindrome. To do this, we can use the equals() function.

fun isPalindrome(number: Int): Boolean {
    val stringNumber = number.toString()
    val reversedStringNumber = stringNumber.reversed()
    return stringNumber.equals(reversedStringNumber)
}

Step 5: Test the function​

To ensure that our function works correctly, we can test it with different numbers. Here are a few examples:

fun main() {
    println(isPalindrome(12321)) // true
    println(isPalindrome(54345)) // true
    println(isPalindrome(12345)) // false
}

When you run the above code, you should see the output true for the first two numbers and false for the last number.

That's it! You now have a function isPalindrome that can check if a number is a palindrome in Kotlin.