Stack with Min/Top | Dataford Interview Questions

Implement a stack with push, pop and top operations.

Asked in the Onsite stage. Implement the required behavior using a stack abstraction.

Contract

Implement execute_stack_operations(operations). Each operation is ['push', value], ['pop'], or ['top']. Return the results of pop and top operations in order. A push produces no result, and pop or top on an empty stack returns None.

Example 1: [['push', 4], ['push', 9], ['top'], ['pop'], ['top']] returns [9, 9, 4] because the most recently pushed value is removed first.

Example 2: [['pop'], ['push', 2], ['top'], ['pop'], ['pop']] returns [None, 2, 2, None].

Constraints

1 <= len(operations) <= 1000
Each operation is ['push', value], ['pop'], or ['top'].
Values are integers.
An empty pop or top returns None.

Function Signature

def execute_stack_operations(operations):

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