# Kotlin Program to Reverse a Number

In this article, we will understand how to print an integer in Kotlin. The reverse of a number is computed using a loop and arithmetic operator % and /.

Below is a demonstration of the same −

Suppose our input is −

The number : 123456

The desired output would be −

The result is 654321

## Algorithm

• Step 1 − START

• Step 2 − Declare two integer values namely myInput and reversed.

• Step 3 − Define the values

• Step 4 − Run a while loop

• Step 5 − Use modulus of 10 and get remainder for ‘myTemp’ .

• Step 6 − Multiply ‘reversed’ with 10, and add to ‘myTemp’, and make that the current ‘reversed’.

• Step 7 − Divide ‘myInput’ by 10, and make that the current ‘myInput'.

• Step 8 − Display the result

• Step 9 − Stop

## Example 1

In this example, we will reverse a number using a while loop. First, let us declare a variable for the input i.e. the number we will reverse. We have also declared a variable for the output i.e. reversed number

var myInput = 123456
var reversed = 0

Now, using a while loop reverse the number. Loop till the input != 0;

while (myInput != 0) {
val myTemp = myInput % 10
reversed = reversed * 10 + myTemp
myInput /= 10
}

Let us now see the complete example to reverse a number using a while loop −

fun main() { var myInput = 123456 var reversed = 0 println("The number is defined as: $myInput") while (myInput != 0) { val myTemp = myInput % 10 reversed = reversed * 10 + myTemp myInput /= 10 } println("The reversed number is:$reversed") }

## Output

The number is defined as: 123456
The reversed number is: 654321

## Example 2

In this example, we will reverse a number.

fun main() { var myInput = 123456 println("The number is defined as: $myInput") reverseNumber(myInput) } fun reverseNumber(input: Int) { var myInput = input var reversed = 0 while (myInput != 0) { val myTemp = myInput % 10 reversed = reversed * 10 + myTemp myInput /= 10 } println("The reversed number is:$reversed") }

## Output

The number is defined as: 123456
The reversed number is: 654321