Python Coding challenge - Day 1085| What is the output of the following Python Code?

 

Code Explanation:

1️⃣ Defining Class Tracker

class Tracker:

A class named Tracker is created.

Objects of this class will inherit its variables and methods.

🔹 2️⃣ Defining a Class Variable

total = 0

total is a class variable.

It belongs to the class itself, not to individual objects.

Internally:

Tracker.total = 0

All instances will use the same variable.

🔹 3️⃣ Defining Method add

def add(self):

add is an instance method.

self refers to the object calling the method (t1 or t2).

🔹 4️⃣ Updating the Class Variable

Tracker.total += 2

This increases the class variable total by 2.

Important:

We are modifying the class variable directly:

Tracker.total

So every object sees the updated value.

🔹 5️⃣ Returning the Updated Value

return Tracker.total

After incrementing, the method returns the new value of total.

🔹 6️⃣ Creating First Object

t1 = Tracker()

Creates an instance named t1.

At this moment:

Tracker.total = 0

🔹 7️⃣ Creating Second Object

t2 = Tracker()

Creates another instance t2.

Both objects share the same variable:

Tracker.total

🔹 8️⃣ Calling the Methods

print(t1.add(), t2.add(), t1.add())

Python executes each call left to right.

Step 1️⃣

t1.add()

Execution:

Tracker.total = 0 + 2

Now:

Tracker.total = 2

Return value:

2

Step 2️⃣

t2.add()

Execution:

Tracker.total = 2 + 2

Now:

Tracker.total = 4

Return value:

4

Step 3️⃣

t1.add()

Execution:

Tracker.total = 4 + 2

Now:

Tracker.total = 6

Return value:

6

✅ Final Output

2 4 6

BOOK: 900 Days Python Coding Challenges with Explanation