# Kotlin Program to Swap Two Numbers

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In this article, we will understand how to how to swap two numbers in Kotlin. This is done using a temporary variable.

Below is a demonstration of the same

Suppose our input is

val1 : 45
val2 : 60


The desired output would be

val1 : 60
val2 : 45


## Algorithm

• Step 1 − Start

• Step 2 − Declare three integers: val1, val2 and tempVal

• Step 3 − Define the values

• Step 4 − Assign val1 to temporary variable

• Step 5 − Assign val2 to val1

• Step 6 − Assign temporary tempVal variable to val2

• Step 7 − Display the two values

• Step 8 − Stop

## Example 1

In this example, we will swap two numbers using a temporary variable −

fun main() {
var val1 = 45
var val2 = 60

println("The first value is defined as: $val1") println("The second value is defined as:$val2")

val tempVal = val1
val1 = val2
val2 = tempVal

println("After swapping")
println("The first value is = $val1") println("The second value is =$val2")
}


## Output

The first value is defined as: 45
The second value is defined as: 60

After swapping
The first value is = 60
The second value is = 45


## Example 2

In this example, we will swap two numbers without using a temporary variable −

fun main() {
var val1 = 25
var val2 = 55

println("The first value is defined as: $val1") println("The second value is defined as:$val2")

val1 = val1 + val2
val2 = val1 - val2
val1 = val1 - val2

println("After swapping")
println("The first value is = $val1") println("The second value is =$val2")
}


## Output

The first value is defined as: 25
The second value is defined as: 55

After swapping
The first value is = 55
The second value is = 25


## Example 3

We can also swap two numbers using the following code

fun main() {
var val1 = 20
var val2 = 10

println("The first value is defined as: $val1") println("The second value is defined as:$val2")

val1 = val1 - val2
val2 = val1 + val2
val1 = val2 - val1

println("After swapping")
println("The first value is = $val1") println("The second value is =$val2")
}


## Output

The first value is defined as: 20
The second value is defined as: 10

After swapping

The first value is = 10
The second value is = 20

Updated on 13-Oct-2022 12:26:30