Python Coding challenge - Day 1296| What is the output of the following Python Code?

 

Code Explanation:

1. Defining the Class

class Counter:

- The class keyword defines a class named Counter.

- A class is a blueprint for creating objects.

- Here, the class will track a shared counter value.

2. Creating a Class Variable

count = 2

- count is a class variable because it is defined inside the class but outside any method.

- Its initial value is 2.

- The variable is shared by instances that access it without creating their own instance attribute.

3. Defining the Constructor

def __init__(self): Counter.count += 1

- __init__() is the initializer method, which runs automatically whenever a new Counter object is created.

- self refers to the current object.

- Counter.count += 1 increases the class variable by 1.

- Each new object therefore increases the shared Counter.count value.

4. Creating the First Object

x = Counter()

- Creates the first object, x.

- The initializer executes and increases Counter.count from 2 to 3.

5. Creating the Second Object

y = Counter()

- Creates another object, y.

- The initializer runs again, increasing Counter.count from 3 to 4.

- At this point, both objects can access the class variable with value 4.

6. Updating x.count

x.count += 5

- Python reads x.count, which currently resolves to the class variable value 4.

- It adds 5, producing 9.

- Python then assigns 9 to x.count, creating an instance variable on x.

- The class variable Counter.count remains 4, and y still reads that class variable.

7. Printing the Values

print(Counter.count, y.count)

- Counter.count accesses the class variable, which is 4.

- y.count also resolves to the class variable because y has no instance attribute named count.

- Therefore, Python prints 4 4.

Final Output

4 4

Book: 100 Python Programs for Beginner with explanation