Reverse Numbers in Python: Guide & Examples

The principle behind reversing the order of numbers in Python is achieved using slicing operations. In Python, slicing operations can be used to obtain a subsequence of sequence types (such as strings, lists, etc.). Slicing operations use the syntax [start:stop:step], where start represents the starting position (default is 0), stop represents the ending position (default is the length of the sequence), and step represents the step size (default is 1).

To reverse the order of numbers, we can set the start and end positions to -1, like [start:stop:step] -> [-1:None:-1]. This will start from the last element of the sequence, decrease the index value gradually by -1, and retrieve elements with a step of -1, achieving a reverse output.

Here is an example code demonstrating how to use slicing to reverse the output of numbers.

# 倒序输出数字
num = 12345
reverse_num = str(num)[::-1]
print(reverse_num)

The output is: 54321.