C++ program for implementation of the stack using singly linked list.

Stack is a list of elements in which insertions and deletions are at the same end of the list called top.

The other end is known as Bottom.Insertion is also known as push,deletion is also known as pop.

The operations performed on a stack are

1)push(): This is the function which is for insertion(pushing)of an element into stack. It is similar to the insertion of an element at the end of a single linked list. See the function insert_end() in the program for operations of single linked list

2)pop(): This is the function which is for deletion(popping up) of an element from the stack. It is similar to the deletion of an element at the end of a single linked list. see the function delete_end() in the program for operations of single linked list

3)stack_display():This is the function which is for displaying the elements of a stack. It is similar to the forward traversal of a single linked list. See the function ftraverse() in the program for operations of single linked list

#include < iostream.h >

#include < stdlib.h >

class stack

{

int element;

stack* next;

public:

stack* push(stack*,int);

stack* pop(stack*);

void stack_display(stack*);

}*head,object;

stack* stack::push(stack* head,int key)

{

stack* temp,*temp1;

temp1=head;

temp=new stack;

temp->element=key;

temp->next=NULL;

if(head==NULL)

head=temp;

else

{

while(head->next!=NULL)

head=head->next;

head->next=temp;

head=temp1;

}

return head;

}

stack* stack::pop(stack* head)

{

stack* temp;

if(head!=NULL)

{

temp=head;

if(head->next==NULL)

{

cout<< ”\nthe pooped element from the stack is: “<< head->element<< endl;

return NULL;

}

while(head->next->next!=NULL)

head=head->next;

cout<< ”the popped element from the stack is “<< head->next->element;

cout<
head->next=head->next->next;

head=temp;

return head;

}

else

{

cout<< ”\nit is impossible to pop an element from the stack as “;

return head;

}

}

void stack::stack_display(stack* head)

{

if(head!=NULL)

{

while(head->next!=NULL)

{

cout<< head->element<<”->”;

head=head->next;

}

cout<< head->element;

cout<< endl;

}

else

cout<< ”the stack is empty\n”;

}

void choice()

{

int key,ch;

cout<< ”\nchoose the operation to be performed\n”;

cout<< ”\n1.push\t2.pop\t3.exit\n\n”;

cin>>ch;

head=NULL;

while(1)

{

switch(ch)

{

case 1:



cout<< ”——————————————————————————–\n”;

cout<< ”\nenter the element to be pushed\n”;

cin>>key;

head=object.push(head,key);

cout<< ”\nthe stack after push operation is \n”;

object.stack_display(head);



cout<<”——————————————————————————–\n”;

break; case 2:

cout<< ”\n“““““““““““““““““““““““““““““““““““““““\n”;

head=object.pop(head);

cout<< ”\nthe stack after pop operation is :\n”;

object.stack_display(head);



cout<< ”\n“““““““““““““““““““““““““““““““““““““““\n”;

break;

case 3:

exit(1);

default:

cout<< ”\nenter the correct choice\n”;

break;

}

cout<< ”\nchoose the operation to be performed\n”;

cout<< ”\n1.push\t2.pop\t3.exit\n”;

cin>>ch;

}

}

void main()

{

choice();

}