A simple Kotlin function to check if a two-digit number is larger than its digit swap.

DigitSwapCompare.kt

import org.junit.Assert.assertEquals
import org.junit.Test

class DigitSwapCompare {

    @Test
    fun testFunction() {
        assertEquals(isLargerOfDigitSwap(14), false)
        assertEquals(isLargerOfDigitSwap(53), true)
        assertEquals(isLargerOfDigitSwap(99), true)
    }

    fun isLargerOfDigitSwap(number: Int) : Boolean {
        if (number < 10 || number > 99)
            throw Exception("Input should be a 2 digit number")

        val firstDigit = number / 10
        val secondDigit = number % 10
        val swap = (secondDigit * 10) + firstDigit
        return number >= swap
    }
    
}