Method Resolution Order (MRO) Basics

Medium Advanced Inheritance & MRO

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Problem Statement

Create classes `A`, `B` inheriting from `A`, `C` inheriting from `A`, and `D` inheriting from `B` and `C`. Define a `greet(self)` method in all of them printing ‘I am [ClassName]’. Instantiate `D` and call `greet()`. Observe which method gets executed.

Input Format

None

Output Format

Print the greeting from the resolved class.

Constraints

None

Sample Output

I am D

Explanation

Python resolves method calls using the Method Resolution Order (MRO), starting with the current class and moving left-to-right, depth-first through base classes.

Starter Code

class A:
    def greet(self): print('I am A')

class B(A):
    def greet(self): print('I am B')

class C(A):
    def greet(self): print('I am C')

# Define D inheriting from B and C
class D:
    pass

if __name__ == '__main__':
    # Instantiate D and call greet()
    pass

Limits

Time Limit: 1s
Memory Limit: 256MB

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