Python Program to Reverse a Number
Last Updated :
24 Jan, 2024
In this article, we will explore two techniques for reversing a number in Python. Various methods exist for creating a Python program to reverse a number, and we will elucidate some commonly employed approaches in this discussion.
Example:
Input: 1234
Output: 4321
Python Program to Reverse a Number
Below are examples of how to reverse a number using a Python program.
Reverse a Number Using For Loop
In this example, in the below code Python function `reverse_number` reverses a given number by iterating through its digits using a for loop. It prints the original and reversed numbers. In the example, the function is applied to the number 6789.
Python3
def reverse_number(number):
original_number = number
reverse = 0
for _ in str (number):
digit = number % 10
reverse = reverse * 10 + digit
number / / = 10
print (f "Original Number: {original_number}" )
print (f "Reversed Number: {reverse}" )
reverse = 6789
reverse_number(reverse)
|
Output :
Original Number: 6789
Reversed Number: 9876
Reverse a Number Using While Loop
In this example, in below code Python code defines a function `reverse_number` that reverses a given number using a while loop. It prints the original and reversed numbers. The example demonstrates applying the function to the number 6789.
Python3
def reverse_number(number):
original_number = number
reverse = 0
while number > 0 :
digit = number % 10
reverse = reverse * 10 + digit
number / / = 10
print (f "Original Number: {original_number}" )
print (f "Reversed Number: {reverse}" )
reverse = 6789
reverse_number(reverse)
|
Output :
Original Number: 6789
Reversed Number: 9876
Reverse a Number Using Recursion
In this example, in below code Python function `reverse_number` recursively reverses a given number by extracting the last digit and placing it at the appropriate position. The recursion continues until the original number is fully reversed. The example demonstrates reversing the number 987654.
Python3
def reverse_number(number):
if number = = 0 :
return 0
else :
return (number % 10 ) * 10 * * ( len ( str (number)) - 1 ) + reverse_number_recursion(number / / 10 )
reverse = 987654
original_number = reverse
reversed_number = reverse_number(reverse)
print (f "Original Number: {original_number}" )
print (f "Reversed Number: {reversed_number}" )
|
Output :
Original Number: 987654
Reversed Number: 456789
Reverse a Number Using String Slicing
In this example, in below code Python code defines a function `reverse_number` that reverses a given number using a list to manipulate its digits. The original and reversed numbers are then printed for an example case where the original number is 1234.
Python3
def reverse_number(number):
num_list = list ( str (number))
reversed_num = int (''.join(num_list[:: - 1 ]))
return reversed_num
original_number = 1234
result = reverse_number(original_number)
print ( "Original Number:" , original_number)
print ( "Reversed Number (List):" , result)
|
Output :
Original Number: 1234
Reversed Number (List): 4321
Share your thoughts in the comments
Please Login to comment...