Question

I need help with a c++ code, i am new learner on stack, please help me write Stack.cpp according to Stack.h provided, thanks(Notes: That data structure is a singly linked list in which pushed items are placed at the tail of the linked list. Similarly, popped items will be removed from the tail of the list.) Actually，I can write a regular one, but i'm not sure how to use the tail in the question.

class Stack {

private:

// Desc: Nodes for a singly-linked list
class StackNode {
public:
int data;
StackNode * next;
};
  

// Desc: head = ptr to the first StackNode (NULL if empty)
// tail = ptr to the last StackNode (NULL if empty)
StackNode * head;
StackNode * tail; //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!please tell me how to use this

public:

// Desc: Constructor
// Post: Stack is empty
Stack();

// Desc: Destructor
// Post: deallocate memory and do other cleanup for the class object and its class members when the object is destroyed
~Stack();

// Desc: Insert element x to the top of the stack.
// Post: add items at the tail of the linked list
void push(int x);

// Desc: Remove and return element at the top of the stack.
// Pre: stack is not empty
// Post: remove items from the tail of the list
int pop();

// Desc: Return the topmost element of the stack.
// Pre: stack is not empty
// Post:
int peek() const;

// Desc: describe if the stack is empty
// Post: return true if empty
bool isEmpty() const;
};

/*Referring to the proposed implementation , could you please analyze the total running time required to push n items to the Stack. Next, analyze the total running time required to pop those n items from the Stack. A detailed analysis is expected, it will be helpful to my learning,:)*/

Answer 1

ans............................................

#include<iostream>
using namespace std;

struct node
{
int data;
struct node *next;
};

class stack
{
struct node *top;
public:
stack()
{
top=NULL;
}
void push();
void pop();
void show();
};
void stack::push()
{
int value;
struct node *ptr;
cout<<" PUSH Operationn";
cout<<"Enter a number to insert: ";
cin>>value;
ptr=new node;
ptr->data=value;
ptr->next=NULL;
if(top!=NULL)
ptr->next=top;
top=ptr;
cout<<" New item is inserted to the stack!!!";

}

void stack::pop()
{
struct node *temp;
if(top==NULL)
{
cout<<" The stack is empty!!!";
}
temp=top;
top=top->next;
cout<<" POP Operation........ Poped value is "<<temp->data;
delete temp;
}

void stack::show()
{
struct node *ptr1=top;
cout<<" The stack is ";
while(ptr1!=NULL)
{
cout<<ptr1->data<<" ->";
ptr1=ptr1->next;
}
cout<<"NULL ";
}

int main()
{
stack s;
int choice;
while(1)
{
cout<<" -----------------------------------------------------------";
cout<<" STACK USING LINKED LIST ";
cout<<"1:PUSH 2:POP 3:DISPLAY STACK 4:EXIT";
cout<<" Enter your choice(1-4): ";
cin>>choice;
switch(choice)
{
case 1:
s.push();
break;
case 2:
s.pop();
break;
case 3:
s.show();
break;
case 4:
return 0;
break;
default:
cout<<" Please enter correct choice(1-4)!!";
break;
}
}
return 0;
}