CareerCup

Linked list.. keep track of top element and the last element's next will be null..

I think it's up to you to answer this question. You can say whatever structure you prefer, if you sure you'll be able to explain how it should be used to implement stack. I use #include <stack> in C++ usually. As for other language (C#) I'd use the structure that has insert and pop operations in constant or logarithmic time.

linked list is the most suitable answer....

basic structures to use are array or link list: using array then you have to maintain index to the current cell (top of stack) and also change size of array when necessary. using link list is more suitable, you add the new node to at the head or delete from the head: more efficient

std::stack<std::deque<type-of-your-choice>>

The answer could be either Linkedlist or Array.

You wont use Array here because, you dont need random access to the elements in the stack which is the advantage of arrays over linked lists.

So, you go for linked lists, which impose no restrictions on the size of the stack.