Anonymous Kotlin function: Check palindrome string

Last update on December 20 2024 12:55:48 (UTC/GMT +8 hours)

Write an anonymous Kotlin function to check if a string is a palindrome.

Sample Solution:

Kotlin Code:

fun main() {
    val isPalindrome: (String) -> Boolean = { str ->
        val cleanStr = str.lowercase().replace(Regex("[^a-zA-Z0-9]"), "")
        cleanStr == cleanStr.reversed()
    }

    val str1 = "Madam"
    val str2 = "Kotlin"

    println("$str1 is a palindrome: ${isPalindrome(str1)}")
    println("$str2 is a palindrome: ${isPalindrome(str2)}")
}

Sample Output:

Madam is a palindrome: true
Kotlin is a palindrome: false

Explanation:

In the above exercise -

Inside "main()" function we define an anonymous function isPalindrome with the type (String) -> Boolean. This function takes a single string argument and returns a Boolean indicating whether the string is a palindrome or not.

The isPalindrome function implements the following steps:

• It converts the input string to lowercase using toLowerCase() to ignore case sensitivity.
• It removes any non-alphanumeric characters from the string using replace(Regex("[^a-zA-Z0-9]"), "").
• It checks if the cleaned string is equal to its reversed version using the == operator.
• The result of the equality comparison is returned as a Boolean value.

Kotlin Editor:

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