Checking Even or Odd Numbers with Kotlin

In Kotlin, determining whether a number is even or odd is a fundamental task. Even numbers are integers that can be divided by 2 with no remainder, while odd numbers leave a remainder of 1 when divided by 2. This article explores two common approaches to achieving this in Kotlin:

1. Using the Modulo Operator (%) with an if Statement

The modulo operator (%) calculates the remainder after a division operation. Here's how you can use it to check for even or odd numbers:

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1fun main() {
2    val number = 10
3
4    if (number % 2 == 0) {
5        println("$number is even")
6    } else {
7        println("$number is odd")
8    }
9}

In this code:

1. We declare a variable number and assign a value to it.
2. The if statement checks if the remainder of dividing number by 2 is equal to 0.
   • If the condition is true (number % 2 == 0), it means number is even, and the message inside the if block is printed.
   • Otherwise, the else block executes, indicating that number is odd.

2. Using an if Expression (Kotlin-Specific)

Kotlin allows if statements to be expressions, meaning they can return a value. This can be used for a more concise even/odd check:

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1fun main() {
2    val number = 15
3    val evenOdd = if (number % 2 == 0) "even" else "odd"
4    println("$number is $evenOdd")
5}

Here, the if expression directly assigns the string "even" or "odd" to the evenOdd variable based on the condition.

Choosing the Right Approach

• If you need a simple check within a larger block of code, the if statement approach with separate blocks might be more readable.
• If you want a more compact solution for assigning the even/odd status to a variable, the if expression is preferable.

Both methods effectively determine even or odd numbers in Kotlin. Select the one that best suits your code's style and purpose.