Python Coding challenge - Day 457| What is the output of the following Python Code?

 

Code Explanation:

 1. Importing defaultdict

from collections import defaultdict

This imports the defaultdict class from Python's collections module.

defaultdict is like a regular dictionary but provides a default value for missing keys.

2. Creating the defaultdict

d = defaultdict(int)

int is passed as the default factory function.

When you try to access a missing key, defaultdict automatically creates it with the default value of int(), which is 0.

3. Incrementing Values

d['a'] += 1

'a' does not exist yet in d, so defaultdict creates it with value 0.

Then, 0 + 1 = 1, so d['a'] becomes 1.

d['b'] += 2

Similarly, 'b' is missing, so it's created with value 0.

Then 0 + 2 = 2, so d['b'] becomes 2.

 4. Printing the Dictionary

print(d)

Outputs: defaultdict(<class 'int'>, {'a': 1, 'b': 2})

This shows a dictionary-like structure with keys 'a' and 'b' and their respective values.

 Final Output

{'a': 1, 'b': 2}