# How to Swap Two Numbers in Swift Program?

This tutorial will discuss how to write a swift program to swap two numbers. Swapping of two variables means mutually exchanging the values of two variables.

## Swapping using temporary variable

Given two variables Number1 and Number2 now we swap their values with each other using a temporary variable Numtemp. It is the most easiest way to swap two numbers.

### Algorithm

The algorithm is explained below −

• Step 1 − Declare three integer variables: Number1, Number2 and Numtemp(temporary variable.)

• Step 2 − Assign values to Number1 and Number2

• Step 3 − Assign Number1 to Numbertemp

• Step 4 − Assign Number2 to Number1

• Step 5 − Assign Numbertemp to Number2

• Step 6 − Display the value of Number1 and Number2 variables

### Example

The following Swift program will show how to swap two numbers using temporary variable.

import Foundation
import Glibc

var Numtemp = 0
var Number1 = 23
var Number2 = 45

print("Number 1 before swapping:", Number1)
print("Number 2 before swapping:", Number2)

Numtemp = Number1
Number1 = Number2
Number2 = Numtemp

print("\nNumber 1 after swapping:", Number1)
print("Number 2 after swapping:", Number2)

### Output

Number 1 before swapping: 23
Number 2 before swapping: 45

Number 1 after swapping: 45
Number 2 after swapping: 23

In the above code, we have two numbers that are Number1 = 23 and Number2 = 45 now we swap them using temporary variable named as Numtemp. The following code will show the swapping −

Numtemp = Number1

Number1 = Number2

Number2 = Numtemp

So the values after swapping are Number1 = 45 and Number2 = 23.

### Example

The following Swift program will show how to swap two numbers using temporary variable.

import Foundation
import Glibc

print("Entered Numbers are-")
print("Number 1- ", Number1)
print("Number 2- ", Number2)

var Numtemp = 0

Numtemp = Number1
Number1 = Number2
Number2 = Numtemp

print("Numbers after swapping-")
print("Number 1-", Number1)
print("Number 2-", Number2)

### Input

Please enter Number 1:
10
20

### Output

Entered Numbers are
Number 1- 10
Number 2- 20
Numbers after swapping
Number 1- 20
Number 2- 10

In the above code, we take two numbers from the user using readLine() function and convert them into integer using Int() function and the entered numbers are number1 = 10 and number2 = 20. Now we swap them using the third variable named as Numtemp. The following code will show the swapping −

Numtemp = Number1

Number1 = Number2

Number2 = Numtemp

So the values of the Number1 and Number2 after swapping are Number1 = 20 and Number2 = 10.