Implement a Stack | Dataford Interview Questions

Paperless Post needs a lightweight stack to process reversible editor actions. Implement a stack that supports adding and removing values while also reporting the current minimum value efficiently.

The input is a list of operations. Each operation is either ["push", value], ["pop"], ["peek"], or ["min"]. Process operations in order and return the results of every pop, peek, and min operation. push operations do not produce an output.

Formal Specification

Implement process_stack(operations), where operations is a list of operation lists. The function returns a list of integers in the same order as the output-producing operations. pop removes and returns the top value, peek returns the top value without removing it, and min returns the smallest value currently in the stack.

Constraints

1 <= len(operations) <= 10^5
-10^9 <= value <= 10^9
Every pop, peek, and min operation is performed on a non-empty stack
Operation names are valid and case-sensitive

Function Signature

def process_stack(operations):

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