IMPLEMENTATION OF STACK

 Stack can be implemented using arrays and pointers.

1. Array implementation
2. Linked List implementation  

1.Array implementation:

                 In this implementation each stack is associated with a pop pointer which is '-1' for empty stack.

• To push an element X onto the stack, Top pointer is incremented and then set stack[Top]=X.
• To pop an element, the stack[Top] value is returned and the top pointer is decremented.
• Pop on an empty stack (or) push on a full stack will exceed the array bounds.

                            

2. Linked List implementation                                                                

• Push  operation is performed by inserting an element at front of the list.
• Pop operation is performed by deleting at the front of the list.
• Top operation returns the element at the front of the list.

                             

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