Solution: Maximum Frequency Stack

Explore the implementation of a maximum frequency stack in C#. Learn how to efficiently track element frequencies using hash maps and stacks to perform push and pop operations in constant time, prioritizing the most frequent and most recently added elements.

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Statement
Solution
- Naive approach
- Optimized approach using frequency counting

Statement

Design a stack-like data structure. You should be able to push elements to this data structure and pop elements with maximum frequency.

You’ll need to implement the FreqStack class that should consist of the following:

FreqStack: This is a class used to declare a frequency stack.
Push(value): This is used to push an integer data onto the top of the stack.
Pop(): This is used to remove and return the most frequent element in the stack.

Note: If there is a tie for the most frequent element, then the most recently pushed element is removed and returned.

Constraints:

$0 \leq$ value $\leq 10^4$
At most, $2 \times 10^3$ ...