 Как перевернуть число в python
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# Как перевернуть число в python

## Как перевернуть число в Python

В этом примере мы преобразуем данное число в строку с помощью str(), а затем поменяем его значение, используя нарезку строки. Перевернутая строка преобразуется обратно в int.

Если данный ввод не является числом, мы напечатаем сообщение пользователю.

### Пример 2: с использованием цикла while

В этой программе мы будем использовать цикл while для перебора цифр числа, выталкивая их одну за другой. Выскочившие цифры добавляются, чтобы сформировать новое обратное числом.

#### Заключение

В этой статье в Python мы узнали, как перевернуть число с помощью цикла while и нарезки строк.

## How to reverse a number in Python [11 Different Ways]

Do you know how to reverse a number in Python? This tutorial will discuss how to reverse a number in Python. And also we are going to cover the following given topics.

• Reverse a number in python
• How we can Reverse a number in Python using for loop
• Reverse a number in Python without using for loop
• Reverse a number in Python using the function
• Reverse a number in Python using a while loop
• How to Reverse a number in Python using recursion
• Reverse a number in Python using an inbuilt function
• Reverse a number in Python without using an inbuilt function
• Reverse a number in Python using slicing
• How to reverse the order of numbers in Python
• How to Reverse a number in a list in Python
• Reverse a number and check if it is a palindrome in Python
• Reverse character in Python

### Reverse a number in python

• When a number is reversed, its digits are arranged so that the first digit comes first, the last digit comes last, the second last digit comes last, and so on, with the last digit coming at the end.
• The list method, slice method, recursion method, and other pre-defined methods in Python can be used in conjunction with conditional statements to create reverse logical functions. The simplest way to carry out this process on any type of user-provided input is with the reverse() method.

Simple logic reversing of numbers in a mathematical way:

First, we will take an integer number and divide it by 10 until the remainder will not come in the reverse order.

Example:

By using the slicing method we can easily get the reversed number of the original input number in Python.

Source Code:

You can obtain the reversed string by using the string-slicing method. Start:stop:step has the value -1. The start point moves to the beginning and stops at the finish when you pass -1 as a step.

Here is the implementation of the following given code This is how we can reverse an input number in Python.

### Reverse a number in Python using for loop

• By utilizing a for loop and the characters from the back of the original string, we may use this technique to reverse a number. In this manner, a new string is created that is inverted since the last character is added first, then the second last, and so on, with the first character being added last.
• Using the input() or raw_input() methods, the input number can be read. Next, determine if the value entered is an integer or not. Now check if the provided number is bigger than zero.
• Create a variable called “reverse” and set its initial value to “0.” Utilizing the mod (%) operator, find the remaining portion for the specified input number. Add the remaining value to the variable reverse after multiplying it by 10.

Example:

Here in this example first, we declare a variable and assign the integer number to it and then used the for loop method along with that len() method.

Here is the Screenshot of the following given code. In this example we have understood how to reverse a number in Python by using the for loop method.

### Reverse a number in Python without using for loop

• This section will discuss how to reverse a number in Python without using for loop.
• The value must first be entered by the user and stored in the variable n. The while loop is executed, and the modulus operator is utilized to determine the number’s final digit. The next digit is then kept at position one, the next to last at position ten, and so forth.
• The final step is to truly divide the number by 10 to eliminate the last digit. When the value of the number is 0, this loop ends and the number is then printed on the back.

Example:

In this example, we will set the condition if the input number is less than to 0 then it will divide by 10 and display the result.

You can refer to the below Screenshot of the following given code This is how we can reverse a number in Python without using the for-loop method.

### Reverse a number in Python using the function

• In this example, we will use the reversed() function to get the reverse of a number in Python.
• The reversed() function returns an object to iterate through the components in reverse order but does not actually reverse anything. The reversed() method provides an iterator to aid in traversing the provided list in reverse order, however it modifies the list.
• In order to reverse a number, we can easily use the Python reversed() function. A pointer that may iterate the string or list in reverse is the function’s return value. After that, we can extract the reversed number from this iterator using Python’s join() method.

Example:

In the following given code first, we declared the input number and then converted the number into string. After that we have used the reversed() function and assign the converted string to it. After executing this code it will display the reverse number of a original number.

Here is the execution of the following given code This is how we can reverse a number in Python using the reversed function.

### Reverse a number in Python using a while loop

• Here we will discuss how to use the while loop concept for getting the reverse number of an original number in Python.
• We need to add the last digit first since we will start a new variable to keep our inverted number. We can take the modulo of the number by ten in the while loop to obtain the final digit. The final digit will reveal the solution to this.

Example:

Here is the Screenshot of the following given code As you can see in the Screenshot we have learned how to use the while loop concept for getting the reverse number of an original number in Python.

### Reverse a number in Python using recursion

• Recursion is used to reverse a number in this way. Recursion has the drawback that it allows for infinite calls to the recursive function until the last index is reached.
• The letters can then be added to the resulting reversed string in this basic instance, which will serve as our starting point. The last index will be inserted first, then the second last index, and so on, with the first index being added at the end. So, by using the recursive function first and then adding the letter, we may reverse the string.

Example:

Here is the Output of the following given code This is how to reverse a number in Python by using the recursion method.

### Reverse a number in Python using an inbuilt function

• Here we discuss how to reverse a number in Python by using the inbuilt function.
• The functions with pre-defined functionality in Python are referred to as built-in functions. There are various functions available for usage on the Python interpreter at all times.
• In this example, we will use the reversed() inbuilt function which is available in Python and Python has a built-in method called reversed that returns an iterator of a sequence that has been reversed.

Example:

Let’s take an example and check how to reverse a number in Python by using the in-built function.

Source Code:

You can refer to the below Screenshot In this example we have understood how to reverse a number in Python by using the inbuilt function.

### Reverse a number in Python using slicing

• In this approach, we’ll reverse the number using string-slicing techniques. The number will first be converted to a string, after which the string will be divided up and added in reverse order using the Python language’s string-slicing capability. We will perform the following operations for a given integer input.
• Change the number’s format to a string and then make use of string slicing to reverse the number.
• By using this technique, we can reverse a number by using the string-slicing method. In Python, slicing is the process of retrieving a string’s substring.

Example:

Let’s take an example and check how to reverse a number in Python by using the slicing method.

Here is the implementation of the following given code As you can see in the Screenshot we have learned how to reverse a number in Python by using the slicing method.

### How to reverse the order of numbers in Python

• In this section, we will discuss How to reverse the order of numbers in Python.
• A number can be reversed by moving an input variable from the back to the front of the input number. When a number is reversed, its digits are arranged so that the first digit comes first, the last digit comes last, the second last digit comes last, and so on, with the last digit coming at the end.

Example:

You can refer to the below Screenshot In this example, we have understood How to reverse the order of numbers in Python.

### Reverse a number in a list in Python

• In this technique, we make use of the fact that lists in Python provide a reverse() method that flips the elements of the list.
• So, using Python’s list() function, we simply add the digits of our number to the list, reverse them to get them in the opposite order, and then join them to get the final reversed number.
• To combine a string with an iterable object, use Python’s join() function. The iterable’s strings are concatenated to create a brand-new string as a result. If the iterable includes any non-string values, it raises a TypeError exception.

Here is the Output of the following given code. This is how we can create a reverse number in a list in Python.

### Reverse a number and check if it is a palindrome in Python

• A palindrome is a word or a set of numbers made up of letters that spell the same word when reading both forward and backward. Python Palindrome permits punctuation, symbols, letters, and spaces within the Palindrome words.
• When reversed, a number must remain the same to qualify as a palindrome. It is not a palindrome if the number does not equal the reverse of itself.

Example:

Here is the Screenshot of the following given code ### Reverse character in Python

• In this section, we will discuss how to reverse a character or string in Python.
• In this example, we will create a slice that goes backward and begins at the end of the string.
• In this instance, the slice phrase [::-1] denotes a move rearward step of one step, starting at position 0 and ending at the end of the string.

Example:

Here is the implementation of the following given code Also, take a look at some more Python tutorials.

In this article, we will discuss how to reverse a number in Python. And also we are going to cover the following given topics.

• Reverse a number in python
• Reverse a number in Python using for loop
• Reverse a number in Python without using for loop
• Reverse a number in Python using the function
• Reverse a number in Python using a while loop
• Reverse a number in Python using recursion
• Reverse a number in Python using an inbuilt function
• Reverse a number in Python without using an inbuilt function
• Reverse a number in Python using slicing
• How to reverse the order of numbers in Python
• Reverse a number in a list in Python
• Reverse a number and check if it is a palindrome in Python
• Reverse character in Python I am Bijay Kumar, a Microsoft MVP in SharePoint. Apart from SharePoint, I started working on Python, Machine learning, and artificial intelligence for the last 5 years. During this time I got expertise in various Python libraries also like Tkinter, Pandas, NumPy, Turtle, Django, Matplotlib, Tensorflow, Scipy, Scikit-Learn, etc… for various clients in the United States, Canada, the United Kingdom, Australia, New Zealand, etc. Check out my profile.

## Python: Reverse a Number (3 Easy Ways) In this tutorial, you’ll learn how to use Python to reverse a number. While this is similar to learning how to reverse a string in Python, which you can learn about here, reversing a number allows us to use math to reverse our number. You’ll learn how to use a Python while loop, string indexing, and how to create an easy-to-read function to reverse a number in Python.

The Quick Answer: Use a Python While Loop ### Reverse a Python Number Using a While Loop

Python makes it easy to reverse a number by using a while loop. We can use a Python while loop with the help of both floor division and the modulus % operator.

Let’s take a look at an example to see how this works and then dive into why this works:

Let’s break down what we do here:

1. We instantiate two variables, number and reversed_number . The first stores our original number and the second is given the value of 0
2. While our number variable is equal to anything by 0 , we repeat our actions below
3. We instantiate digit , and assign it the modulus (remainder) of our number divided by 10
4. We multiply our reversed number by 10 and add our digit
5. Finally, we return the floored result of our number divided by 10 (this essentially removes the number on the right)
6. This process is repeated until our original number is equal to zero

It’s important to note, this approach only works for integers and will not work for floats.

In the next section, you’ll learn how to use Python string indexing to reverse a number.

### Reverse a Python Number Using String Indexing

Another way that we can reverse a number is to use string indexing. One of the benefits of this approach is that this approach will work with both integers and floats.

In order to make this work, we first turn the number into a string, reverse it, and turn it back into a number. Since we’ll need to convert it back to its original type, we need to first check the numbers type.

Let’s take a look at how we can accomplish this in Python:

Python indexing allows us to iterate over an iterable object, such as a string. The third parameter is optional, but represents the step counter, meaning how to traverse an item. By default, the value is 1 , which means it goes from the first to the last. By using the value of -1 , we tell Python to generate a new string in its reverse.

In the next section, you’ll learn how to create a custom function that makes the code easier to follow and understand.

### Reverse a Python Number Using a Custom Function

In this section, you’ll learn how to turn what you learned in the section above into an easy-to-read function. While the code may seem intuitive as we write it, our future readers may not agree. Because of this, we can turn our code into a function that makes it clear what our code is hoping to accomplish.

Let’s take a look at how we can accomplish this in Python:

Our function accepts a single parameter, a number. The function first checks what the type is. If the type is either float or int , it reverses the number and returns it back to the same type. If the type is anything else, the function prints out that the type is neither a float nor an int.

### Conclusion

In this post, you learned how to reverse a number using both math and string indexing. You also learned how to convert the string indexing method to a function that will make it clear to readers of your code what your code is doing.

If you want to learn more about string indexing in Python, check out the official documentation for strings here.

## Reverse Number in Python

By Mahantesh Nagathan ### Introduction to Reverse Number in Python

Reverse operation in python can be defined as a process of turning the order of the input assigned to a variable from back to front or front to back. This operation can be achieved by any kind of logic involving the conditional statements of python, such as for loop, while conditional statement, if condition, etc. There are multiple pre-defined methods in python which can be worked along with the conditional statements for creating reverse logical function, and they are list method, slice method, recursion method, etc. Reverse() method is the straightforward method for performing this operation for any kind of input provided by the user.

#### Logic for Reverse Number in Python

The below points briefly us about how to reverse a given number in python:

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• The input number can be read by using input () or raw_input () method.
• Next, check whether the entered value is an integer or not.
• Now check whether a given integer is greater than 0 or not.
• Create a variable called reverse and initialize the variable value with 0.
• Now find the remainder for the given input number by using the mod (%) operator.
• Multiply the variable reverse with 10 and add the remainder value to it.
• Now floor (floor division is performing the division operation and resulting value provides lower integer to the value) divide the given input number with 10.
• The given input number will become 0 at some point.
• Now repeat the steps 5, 6, 7 until you get the input number is not greater than zero.
• In the last step, display the variable in reverse.

#### Reversing the Number Using different ways in Python

Below are the different ways in Python:

##### 1. Using Slicing Method

Code:

Execution Steps:

• Save the python code in your drive. (Here, we have used D drive for executing the programs)
• Now open the command prompt and locate your drive.
• Execute the program with the command as python program_name.py
• The python programs will be saved with .py extension.

Output: ##### 2. Using For loop Method

Code:

Output: ##### 3. While Loop Method

Code:

Output: ##### 4. Using Reversed Method

Code:

Output: ##### 5. Using user-entered number and then reversing it

Code:

Output: ##### 6. Two-Digit Reverse Method

Code:

Output: ##### 7. Three-Digit Reverse Method

Code:

Output: ##### 8. Without the Recursion Method

Code:

Output: ##### 9. With Recursion Method

Code:

Output: ##### 10. Using Function Method

Code:

Output: ##### 11. Using List Method

Code:

Output: ##### 12. Using the Stack Method

Code:

Output: #### Conclusion

So far in this tutorial, we have learned to find the reverse number of a given number in python. This program runs only once, i.e. it asks the user to enter a number, find the reverse value, print and exit. We can also insert it into an infinite loop for continuous reading of a new number from the user. Put it in an infinite loop and check what’s going on.

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