Swapping of two numbers without third variable in python

Introduction

Swapping two variables means exchanging the value of two variables with each other. This can be easily done with the third variable, but we must not use the third variable here. Let's see how this problem can be solved.

Solution 1

Using arithmetic operator.

Code

# variables
var1 = 33
var2 = 44
print(f"Before swapping, var1={var1} & var2={var2}")

# Swapping operation
var1 = var1 + var2
var2 = var1 - var2
var1 = var1 - var2
print(f"After swapping, var1={var1} & var2={var2}")

Output

Before swapping, var1=33 & var2=44
After swapping, var1=44 & var2=33

Solution2

Using multiplication and division operators.

Code

# variables
var1 = 88
var2 = 45
print(f"Before swapping, var1={var1} & var2={var2}")

# Swapping operation
var1 = var1 * var2
var2 = var1 / var2
var1 = var1 / var2
print(f"After swapping, var1={int(var1)} & var2={int(var2)}")

Output

Before swapping, var1=88 & var2=45
After swapping, var1=45 & var2=88

Solution 3

Using XOR operator.

Code

# variables
var1 = 15
var2 = 18
print(f"Before swapping, var1={var1} & var2={var2}")

# Swapping operation
var1 = var1 ^ var2
var2 = var1 ^ var2
var1 = var1 ^ var2
print(f"After swapping, var1={var1} & var2={var2}")

Output

Before swapping, var1=15 & var2=18
After swapping, var1=18 & var2=15

Solution 4

Using a python trick.

Code

# variables
var1 = 25
var2 = 38
print(f"Before swapping, var1={var1} & var2={var2}")

# Swapping operation
var1, var2 = var2, var1
print(f"After swapping, var1={var1} & var2={var2}")

Output

Before swapping, var1=25 & var2=38
After swapping, var1=38 & var2=25