You can access characters in a string using __negative indexing__, which starts from the end of the string.

This is especially useful when you want to get the __last character__ or work backwards, without manually counting the total length of the string.

## Syntax

```python
string[-1]   # Last character  
string[-2]   # Second-to-last character  
string[-3]   # Third-to-last character
```

Negative indexing starts at `-1`.
`string[-1]` returns the last character,
`string[-2]` returns the second-to-last, and so on.
`string[-0]` is the same as `string[0]` (first character), so it's rarely used.

## Example

document = "Invoice #34567"
last_char = document[-1]
print(last_char)  # Output: 7

In this case, we don't need to count the total number of characters to find the last one.
We simply use `-1` to get the final digit of the invoice number.

import unittest
import sys
from io import StringIO


class TestUserCode(unittest.TestCase):
    def _test_variable_equals_string(self, var_name, expected):
        import user_code
        if not hasattr(user_code, var_name):
            return (False, f"Expected '{var_name}' variable to be defined.")
        var = getattr(user_code, var_name)
        if var != expected:
            return (False, f"Expected '{var_name}' to equal '{expected}', but got '{var}'.")
        return (True, f'The variable {var_name} equals "{expected}"')

    def test_last_char(self):
        passed, result_text = self._test_variable_equals_string(
            'last_char', '8')
        self._testMethodName = result_text
        self.assertTrue(passed, result_text)

    def test_second_last_char(self):
        passed, result_text = self._test_variable_equals_string(
            'second_last_char', '4')
        self._testMethodName = result_text
        self.assertTrue(passed, result_text)


if __name__ == '__main__':
    unittest.main()

test_main.py

This course is going to help you dive deeper into data types and try to work with them. Here you will learn basic operations and all ins and outs of numbers, boolean data type, and strings. This course consists of a lot of practical tasks after which you will become a skillful programmer.

Numeric data types are crucial in Python, so it is important to start with them. Here you will work with simple math operations and find out the purposes of learning different types of numerical data.

Mastering boolean data types and logical operations in Python. You'll learn how to work with True and False, apply logical operators like and, or, and not, and understand how operator precedence works in complex expressions.

Strings are an essential part of Python programming, allowing you to work with text data. In this section, you'll learn how to manipulate strings, extract characters, slice words, and search for specific phrases.

This chapter consists of practical tasks that combine all the examined topics together with a bit of theory.

Negative Indexation

Syntax

Example

Lösung

Negative Indexation

Syntax

Example

Lösung