Max Stack

Try to solve the Max Stack problem.

Statement

Design a custom stack class, Max Stack, that supports the basic stack operations and can find the maximum element present in the stack.

Implement the following methods for Max Stack:

  • Constructor: This initializes the Max Stack object.

  • Void Push(int x): This pushes the provided element, x, onto the stack.

  • Int Pop( ): This removes and returns the element on the top of the stack.

  • Int Top( ): This retrieves the most recently added element on the top of the stack without removing it.

  • Int peekMax( ): This retrieves the maximum element in the stack without removing it.

  • Int popMax( ): This retrieves the maximum element in the stack and removes it. If there is more than one maximum element, remove the most recently added one (the topmost).

Constraints:

  • −1000≤-1000 \leq x ≤1000\leq 1000

  • A maximum of 100100 calls can be made to Push( ), Pop( ), Top( ), peekMax( ) and popMax( ).

  • The Pop( ), Top( ), peekMax( ), and popMax( ) methods will always be called on a non-empty stack.

Examples

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