Kotlin Program to Check Whether a Number is Even or Odd

In this program, you'll learn to check if a number entered by an user is even or odd. This will be done using two variants of if...else in Kotlin.

Example 1: Check whether a number is even or odd using if...else statement

import java.util.*

fun main(args: Array<String>) {

    val reader = Scanner(System.`in`)

    print("Enter a number: ")
    val num = reader.nextInt()

    if (num % 2 == 0)
        println("$num is even")
    else
        println("$num is odd")
}

When you run the program, the output will be:

Enter a number: 12
12 is even

In the above program, a Scanner object, reader is created to read a number from the user's keyboard. The entered number is then stored in a variable num.

Now, to check whether num is even or odd, we calculate its remainder using % operator and check if it is divisible by 2 or not.

For this, we use if...else statement in Java. If num is divisible by 2, we print num is even. Else, we print num is odd.

We can also check if num is even or odd by using if...else as an expression.


Example 2: Check whether a number is even or odd using if...else expression

import java.util.*

fun main(args: Array<String>) {

    val reader = Scanner(System.`in`)

    print("Enter a number: ")
    val num = reader.nextInt()

    val evenOdd = if (num % 2 == 0) "even" else "odd"

    println("$num is $evenOdd")
}

When you run the program, the output will be:

Enter a number: 13
13 is odd

Unlike Java, in Kotlin if...else statements are also expressions. So, you can store the return value from if...else statement to a variable. This is a substitute of Java's ternary operator (? :)  in Kotlin.

Here's the equivalent code in Java: Check Whether a Number is Even or Odd in Java

In the above program, if num is divisible by 2, "even" is returned. Else, "odd" is returned. The returned value is stored in a string variable evenOdd.

Then, the result is printed on the screen using println().