Swap two variables using function in Python

February 4, 2021

Swap two variables using functions

Swap of two variables using function in Python can be done by passing our variables to the user defined function as arguments and returning or printing the swapped data.

Regarding arguments and returning values , functions are 4 types

With arguments and return value
With arguments and without return value
Without arguments and with return value
Without arguments and without return value

Working

Step 1: define a function swap
Step 2: read two input variables
Step 3: As per the type of function , pass argument and return the swapped value
Step 4:Print swapped value

Python code: Swap two variables using function in Python

With arguments and return value:

def swap(x,y): 
    print(“Before swapping a :”,x)
    print(“Before swapping b :”,y)
    #logic to swap without using third variable 
    x,y=y,x
    return x,y 

a=int(input(“Enter value : “))
b=int(input(“Enter value : “))    
a,b=swap(a,b) 
print(“After swapping a becomes :”,a)
print(“After swapping b becomes :”,b)

With arguments and without return value:

def swap(x,y): 
    print(“Before swapping a :”,x)
    print(“Before swapping b :”,y)
    #logic to swap without using third variable 
    x,y=y,x
    print(“After swapping a becomes :”,x)
    print(“After swapping b becomes :”,y)

a=int(input(“Enter value : “))
b=int(input(“Enter value : “))  

swap(a,b)  

Without arguments and with return value:

def swap(): 
    x=int(input(“Enter value : “))
    y=int(input(“Enter value : “))  
    print(“Before swapping a :”,x)
    print(“Before swapping b :”,y)
    #logic to swap without using third variable 
    x,y=y,x
    return x,y
    
a,b=swap()
print(“After swapping a becomes :”,a) 
print(“After swapping b becomes :”,b)  

Without arguments and without return value:

def swap(): 
    x=int(input(“Enter value : “))
    y=int(input(“Enter value : “))  
    print(“Before swapping a :”,x)
    print(“Before swapping b :”,y)
    #logic to swap without using third variable 
    x,y=y,x 
    print(“After swapping a becomes :”,x) 
    print(“After swapping b becomes :”,y)  
   
swap()

Enter value : 123
Enter value : 456
Before swapping a : 123
Before swapping b : 456
After swapping a becomes : 456
After swapping b becomes : 123