What is Stack and How to Implement Stack? Reverse Array without using inbuild Function. Check whether the number is palindrome or not. OOPS Concepts (In Detail).

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A stack is a data structure that follows the Last In First Out (LIFO) principle. It can be implemented using arrays or linked lists.

To implement a stack using arrays, we can use an array and a pointer to keep track of the top element.
Example: Push operation - increment the pointer and add the element at that index. Pop operation - return the element at the top index and decrement the pointer.
To reverse an array without using inbuilt functions, we can use two pointers starting from the beginning and end of the array and swap elements until they meet.
Example: Input array [1, 2, 3, 4, 5], after reversal [5, 4, 3, 2, 1].
To check if a number is a palindrome, we can convert it to a string and compare it with its reverse.
Example: Input number 121, after reversing 121, which is equal to the original number, hence it is a palindrome.
OOPS concepts include Abstraction, Encapsulation, Inheritance, and Polymorphism.
Example: Abstraction - hiding the internal implementation details and showing only the necessary features to the outside world.

What is Stack and How to Implement Stack? Reverse Array without using inbuild Function. Check whether the number is palindrome or not. OOPS Concepts (In Detail).

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