Heap data structure can be implemented either using arrays or trees. By default, all the global variables are stored in the heap memory. Heap is also a data structure or memory used to store the global variables. If we perform pop operation, then the topmost element, i.e., 1 would be removed from the stack as shown below: What is Heap? Since element 1 comes above the element 2, so element 1 would be considered the top of the stack. If we want to insert 1 element in the stack, then the stack would like:

Since there is only one element in the stack, so 2 element would be at the top of the stack. After push operation, the stack would look like: Suppose we want to insert 2 element in the stack. Now we will perform push and pop operations on the stack. The above representation is an empty stack and let's assume that stack is 's'. It can be represented logically as a three-sided figure as a container open from one side. We can observe in the above figure that stack looks like a container which is opened from one side. Pop(): It removes the most recent element from the stack.

Pop: The process of deleting an element from the stack is known as a pop operation.

Push(x): It inserts an element x into the stack.

Push: The process of inserting an element in a stack is known as push operation.

The following are the two operations available with a stack ADT: It follows LIFO (Last In First Out) principle in which recently added element must be removed from the stack first.Ī stack is a list or a collection with a restriction that the insertion and deletion will take place from one end known as the top of the stack. In other words, we can say that only top of the stack is accessible and any item can be removed or inserted from the top of the stack. It cannot be considered as the property rather it is considered as the constraint or restriction applied to the stack. Stack is a collection with a property that an item or an object must be removed from one end known as the top of the stack. Some examples of stack of real world are stack of dinner plates, mathematical puzzle known as Tower of Hanoi containing three rods having multiple discs and stack of tennis balls. Stack is similar to the stack a way organizing the objects in the real world.

What is Stack?Ī Stack is a data structure that is used for organizing the data. Before understanding the differences between the Stack and Heap data structure, we should know about the stack and heap data structure separately.

Queue vs stack vs heap