🧠 Garbage Collection & Reference Counting in Python

Python automatically manages memory. 
Objects are deleted when they are no longer used.

📌 Reference Counting

Every object tracks how many variables point to it. 
When the count becomes 0, it is removed.

a = [1, 2, 3]
b = a

del a
del b

Reference count:
a → 1
a, b → 2
after del → 0
Object deleted

📌 Circular Reference Problem

Two objects pointing to each other 
will never reach reference count 0.

class Node:
    def __init__(self):
        self.ref = None

a = Node()
b = Node()

a.ref = b
b.ref = a

del a
del b

Both objects still reference each other
Reference count ≠ 0

📌 Garbage Collector (GC)

Python’s GC:
• Detects unreachable cycles 
• Breaks circular references 
• Frees memory safely 

🎯 Core Idea

Reference Counting → Main mechanism 
GC → Handles circular references