Stack ADT and Operations A Stack ADT is a data structure that follows a LIFO (Last-In, First-Out) paradigm. This means that the newest element is always...
A Stack ADT is a data structure that follows a LIFO (Last-In, First-Out) paradigm. This means that the newest element is always added to the top of the stack, and the oldest element is always removed from the top.
Operations:
Push (pushing an element onto the top of the stack):
The new element is added to the top of the stack.
The new element replaces the oldest element at the top.
The stack pointer is updated to point to the new top element.
Pop (removing the top element from the stack):
The top element is removed from the stack.
The oldest element is removed from the top of the stack.
The stack pointer is updated to point to the element just below the top.
Applications:
Reverse order traversal of a linked list:
Push the nodes of the linked list onto the stack.
Pop the nodes from the stack in reverse order.
Print the nodes in the reverse order they were stored.
Implement a compiler:
Push the operator symbols onto the stack.
Pop the operator symbols from the stack in the correct order.
Evaluate the expression by performing the corresponding operations.
Undo and redo functionality:
Push the actions to be undone onto the stack.
Pop the actions from the stack in the order they were pushed.
Undo the last action by removing it from the stack.
Examples:
push 5
pop
push A
push B
push C
pop A
pop B
push D
pop C
Benefits of using a Stack ADT:
Efficiency: Push and pop operations are constant, regardless of the size of the stack.
Last-in, First-out behavior: The top element is always the oldest element.
Simple implementation: The stack can be implemented using a few simple pointers and a single stack pointer