Solution: Min Stack

Explore how to design a custom Min Stack data structure that supports push, pop, and retrieval of the minimum element all in constant time. Understand the use of two stacks—one for storing actual values and the other for tracking current minimums—to implement efficient operations suitable for coding interviews.

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Statement
Solution
- Time complexity
- Space complexity

Statement

Design a custom stack class, Min Stack, allowing us to push, pop, and retrieve the minimum value in constant time. Implement the following methods for Min Stack:

Constructor: This initializes the Min Stack object.
Pop(): This removes and returns from the stack the value that was most recently pushed onto it.
Push(): This pushes the provided value onto the stack.
Min Number(): This returns the minimum value in the stack in $O(1)$ time.

Note: The time complexity of all the methods above should be $O(1)$ . ...