Python Coding challenge - Day 227 | What is the output of the following Python Code?

 

Code:

s = "immutable"

s[1] = 'n'

print(s)

Solution and Explanation:

The code snippet you provided is attempting to demonstrate a fundamental property of Python strings: their immutability.

Let's break it down step by step:

Assigning the String:

s = "immutable"

Here, we assign the string "immutable" to the variable s. Strings in Python are sequences of characters and are immutable, meaning once a string is created, its content cannot be changed.

Attempting to Modify the String:

s[1] = 'n'

This line tries to change the character at index 1 of the string s from 'm' to 'n'. However, because strings are immutable, this operation is not allowed in Python. Attempting to assign a new value to a specific index of a string will raise a TypeError.

Printing the String:

print(s)

This line prints the current value of s. However, because the previous line raises an error, this line will not be executed unless the error is handled.

Let's see what happens if we run this code:

s = "immutable"

s[1] = 'n'  # This line will raise an error

print(s)  # This line will not be executed because of the error above

When you run this code, Python will raise an error at the line s[1] = 'n', and the error message will be something like this:

TypeError: 'str' object does not support item assignment

This error message indicates that you cannot assign a new value to an individual index in a string because strings do not support item assignment.

If you need to modify a string, you must create a new string. For example, if you want to change the second character of s to 'n', you can do it by creating a new string:

s = "immutable"

s = s[:1] + 'n' + s[2:]

print(s)

This code will correctly print innutable, as it constructs a new string by concatenating parts of the original string with the new character.