What is the meaning of int a -1 in Python

Question

I cannot understand this. I have seen this in people's code. But cannot figure out what it does. This is in Python.
str(int(a[::-1]))

Answer 1

Assumming a is a string. The Slice notation in python has the syntax -

list[<start>:<stop>:<step>]

So, when you do a[::-1] , it starts from the end, towards the first, taking each element. So it reverses a. This is applicable for lists/tuples as well.

Example -

>>> a = '1232' >>> a[::-1] '2321'

Then you convert it to int and then back to string (Though not sure why you do that) , that just gives you back the string.